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TIM SKWIAT, Pn2

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11 FOODS FOR AMAZING SEX

Let’s talk about sex for now to the people at home or in the crowdIt keeps coming up anyhow

Don’t decoy, avoid, or make void the topicCuz that ain’t gonna stop it

Now we talk about sex on the radio and video showsMany will know anything goes

Let’s tell it how it is, and how it could beHow it was, and of course, how it should be…

Let’s talk about sex. – Salt-n-Peppa

They talk about it on the radio. They talk about it—and do it—on TV and in movies. However, for some reason or another, sex still has a bit of a stigma attached to it that makes it somewhat of a “taboo” subject. Let’s face it: Sex is a key component of a healthy lifestyle. Heck, many people work really hard to get in shape just so they can have more sex and do it better.

According to journalist Kara Meyer Robinson, “Sex not only feels good. It can also be good for you.”1 In fact, Robinson shares ten “surprising health benefits of sex”:

1. Helps keep your immune system working optimally. In one study published in the journal Psychological Reports, psychologists from Wilkes University found that college students who had sex 1 – 2 times per week had higher levels of immunoglobulin A (IgA), which is a key antibody that plays a crucial role in immune system function, compared to students who had sex less often.2

2. Boosts your libido. This goes along the lines of the “use it or lose it” mantra. Having sex leads to better sex and an increased libido.

3. Improves women’s bladder control. “Good sex is like a workout for your pelvic floor muscles.”

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4. Lowers your blood pressure. Multiple studies have shown that sex can lower systolic blood pressure.3

5. Counts as exercise. When it comes to exercise, many experts suggest that you should find something that you enjoy doing. Although it isn’t a replacement for strength training or aerobic conditioning, sex is indeed a form of exercise that boosts heart rate and (generally) involves using a variety of the body’s muscles.

6. Lowers heart attack risk. In one study published in The American Journal of Cardiology, researchers at the New England Research Institute in Massachusetts found that men who had sex at least twice a week cut their risk for heart disease in half.4

7. Lessens pain. The old saying that “motion is lotion” rings true, but also, sexual intercourse and having an orgasm result in the release of various “feel good” hormones and neurotransmitters that can ease pain.

8. May make prostate cancer less likely. In one study published in the Journal of the American Medical Association, researchers found that men who ejaculated frequently (≥ 21 times/month) significantly reduced their risk of developing prostate cancer.5

9. Improves sleep. Some folks may be more “guilty” of this than others (that’s you, gentlemen). Some of those same feel-good hormones that ease pain can also help promote a sense of relaxation that makes falling asleep easier.

10. Eases stress. As you’ll see, the act of touching and engaging in the physical activity of sex can lead to the release of a special “love hormone” that can also combat stress.

With all of that in mind, you might be asking, “What foods should I eat to enjoy better sex?” That would be a fantastic question, and the fact of the matter is that there’s probably not one single food that’s the “key” to better sex. Rather, just like optimizing body composition, overall health, and performance, your sexual health and performance are contingent on your entire body of “nutrition work.” In other words, there’s no “magic bullet.”

Your overall body of nutrition work can have a tremendous impact on the hormones and brain chemicals (i.e., neurotransmitters) that play crucial roles in optimizing sexual behaviors and performance. However, there’s not one single hormone or neurotransmitter that’s necessarily the “key” to better sex. More likely, it’s the

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interconnection of hormones, neurotransmitters, and one’s overall lifestyle choices—which includes your nutrition behaviors and food choices—that impact sexual health and function.

Remember, there are other factors that influence libido, sex drive, and motivation. In fact, in a recent study published in the journal Archives of Sexual Behavior, researchers from the Department of Psychology at the University of Texas surveyed 3,000 men and women who reported 237 different reasons for engaging in sex.6 The reasons were divided into four domains:

• Love and intimacy• Pleasure (e.g., sexual libido, desire)• ‘Mate guarding’ (e.g., preventing loss or impairment of a relationship)• Nefarious reasons (e.g. job promotion, money)

Along those lines, there is a laundry list of factors that may impair one’s libido, including age, low mood, low self-image, fear of appearing sexually substandard, fear of negative outcome, negative feelings toward the partner, sexual and nonsexual distractions, fatigue, depression, and even certain medications.7–12

What does all of that have to do with this? Well, there’s more than food to the equation, as your (and your partner’s) emotional wellbeing and the quality of your intimate relationships play a tremendous role in sexual health and activity. Taking time to improve your relationships and demonstrating to your partner that you genuinely care may have a significant impact on his/her sexual desire. Remember, it takes two to tango.

You might start with the art of non-sexual touch. Yep, that means caringly touching your partner without having sexual motivation or expectation. You might even start with a random, unexpected hug. Speaking of which…

Oxytocin is widely referred to as the “love hormone,” as well as the “hug hormone” and the “cuddle chemical,” due to its effects on behavior, including its role in love and reproduction. It’s well known that, in women, oxytocin is released during childbirth and breastfeeding. For these reasons, researchers have referred to oxytocin as “the great facilitator of life.”13 But, there’s much more to oxytocin.

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Researchers now believe that oxytocin is involved in a wide variety of physiological functions, including sexual activity, penile erection, ejaculation, social bonding, stress, and likely many more, making oxytocin a very important topic of discussion when it comes to sexual health and function.14

The good news is that childbirth and stimulation of a woman’s nipples aren’t the only way to boost oxytocin. Indeed, one of the most impactful ways to boost oxytocin is to give someone a hug, and studies show that greater partner support, including more frequent hugs, results in greater levels of oxytocin.15,16 In fact, neuroeconomist, prolific author, and oxytocin expert Dr. Paul Zak recommends that you give/receive at least eight hugs a day.17

Dr. Zak and his colleagues at the University of San Diego further demonstrated the importance of touch on oxytocin release in a recent study published in the journal Alternative Therapies in Health and Medicine when they found that getting a massage not only reduces levels of stress hormones, it also results in a spike in oxytocin levels.18 Dancing and praying have all been shown to raise oxytocin levels, and believe it or not, using Twitter and Facebook can boost oxytocin levels. That’s right, Dr. Zak found that 100% of folks he tested experienced a spike in oxytocin when using social media.19

Another way to boost oxytocin levels is to give someone a gift, which increases their levels of the “love hormone.” Doing something nice like giving an unexpected gift—or flowers—not only fortifies the relationship, it also contributes to boosting this “cuddle chemical.”19 Maybe you might consider surprising your partner with a massage and deliver the gift with a hug to boot!

There’s even more to oxytocin that relates to the discussion of better sex. Dr. Zak and others also refer to oxytocin as the “moral molecule” due to its role in the development of trust and building healthy, stable relationships.20 As mentioned above, the intimacy and quality of your relationship with your partner plays an intricate role in sexual behavior and activity.

Along these lines, oxytocin has been shown to increase fidelity in men. In one study published in the Journal of Neuroscience, researchers found that men in monogamous relationships who were given a boost of oxytocin interacted with single women at a greater physical distance then men who weren’t given any oxytocin.21

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In addition, as you’ll see in a moment, there may also be certain foods that you can eat—and of course, share and enjoy with your partner—that may boost levels of oxytocin.

Testosterone is critical in male sexual behavior, reproduction, sexual function, and libido, and what’s more, it also has important beneficial effects on muscle mass and strength, adiposity, bone density, and vigor and well-being.22 Along those lines, low testosterone is linked to poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue—all factors that directly tie to sexual desire and function.23 Clearly, this is an important sex chemical to discuss and to optimize for sexual health and function.

Ladies, before you jump ahead and skip this section, while testosterone is typically considered a “male hormone,” it is NOT just for men. That’s right, several studies have demonstrated that testosterone levels in women are closely correlated to libido, and declining levels of testosterone lead to significant reductions in a woman’s sexual desire.24–26 What’s more, multiple studies have found that women who are given testosterone therapy (under a physician’s supervision, of course) show significantly improved sexual function and desire.24,27,28 Not only that, researchers have found that just thinking about sex increases levels of testosterone in women, highlighting its importance in female sexual behavior.29

Simply put, women also need healthy levels of testosterone to support sexual function and libido.

The great news is that there are a number of dietary factors that can help optimize testosterone levels, and you can start by making sure that you’re eating enough dietary fat. In a seminal study published in the prestigious Journal of Applied Physiology, researchers from Penn State University found that testosterone levels in men were positively related to their intakes of total fat, saturated fat, and monounsaturated fat.30 In other words, the men with higher intakes had higher testosterone levels. In fact, men who consumed 30% of their calories from fat had 33% and 67% higher levels of testosterone than men who consumed only 20% or 15% of their calories from fat, respectively.

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Other studies have demonstrated similar findings, showing significant decreases in testosterone levels when both men and women consume a diet containing 20% of calories from fat compared to a diet containing 40% of fat.31–34 Along those same lines, low-fat diets have been shown to result in significant decreases in testosterone.35 Vegetarians, who tend to consume less total and saturated fat, also demonstrate lower levels of testosterone compared to their meat-eating counterparts.36–38

With that in mind, a good starting point for most folks to optimize testosterone appears to be consuming between 30 – 40% of total calories from fat. In a moment, you will see some of the best foods to eat to optimize fat intake and testosterone.

Another key nutrient that appears to be closely tied to testosterone levels is vitamin D. The “sunshine vitamin” is involved in much more than just building and maintaining healthy bones. You see, the bioactive form of vitamin D actually functions as a hormone itself, and along those lines, vitamin D is much more than an essential vitamin: it’s a prohormone.39 Nearly every tissue in the body has a vitamin D receptor, including the pancreas, immune system, skin, thyroid, stomach, colon, an array of the reproductive tissues (including ovaries, uterus, prostate, testis, and sperm), and more.40–43

In a recent study published in the European Journal of Endocrinology, researchers from the University of Manchester in England examined the relationship between vitamin D levels and testosterone concentrations in over 3,300 middle-aged and elderly men. They found that men with low levels of vitamin D (defined by blood testing below 50nmol/L) had significantly lower levels of testosterone.44 Overall, they found that vitamin D levels were positively associated with both total and free testosterone and negatively associated with estrogen.

Additional studies have also shown a positive correlation between vitamin D levels and testosterone, with low levels of vitamin D being associated to low levels of testosterone.45–47 Even more, research shows a distinct seasonal variation in testosterone levels that closely resembles the seasonal variation in levels of vitamin D, a consequence of seasonal differences in sunlight-induced vitamin D production in the skin.47,48

In one recent 12-month, double-blind, randomized control trial published in the

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journal Hormone and Metabolic Research, Austrian researchers found that males supplementing with 3332 IU/day of vitamin D had a significant increase in total testosterone, bioactive testosterone, and free testosterone levels.49 These findings fortify the correlation between vitamin D and testosterone, suggesting that optimal vitamin D levels may play an intricate role in maximizing testosterone production.

Unfortunately, most people don’t get nearly enough sunlight (especially with their bare skin exposed), and beyond that, where you live, the time of year, and the time of day can all dramatically influence the amount of the sun’s UVB rays that enter the earth’s atmosphere and your exposure to them (i.e., seasonal variation). With that in mind, it’s critical to use diet and supplementation to help optimize vitamin D levels, and in just a moment, you’ll see some of the best dietary sources of this crucial nutrient.

Two minerals that play a key role in maintaining healthy testosterone levels are magnesium and zinc. In fact, in one study, researchers found that athletes engaging in intense physical activity who were given a simple zinc-magnesium supplement (30mg zinc, 450mg magnesium, and 10.5mg of vitamin B-6) increased their testosterone levels by 33% over the course of 8 weeks whereas the placebo group actually experienced a 10% decrease.50

Magnesium is involved in over 300 enzymatic reactions and biological processes, and there is convincing evidence that magnesium exerts a positive influence on sex hormone status, including testosterone.51 In one study published in the International Journal of Andrology, researchers from the University of Parma measured the magnesium and hormone levels (including testosterone) of nearly 400 older Italian men, and they found that magnesium levels were strongly associated with testosterone levels (i.e., greater magnesium = higher testosterone).52

Additionally, researchers from Turkey found that men (both sedentary and active) supplementing with magnesium for 4 weeks experienced a significant increase in both free and total testosterone.53 Interestingly, French researchers have found that magnesium may help increase levels of bioactive testosterone by reducing how much testosterone binds to a molecule called sex hormone-binding globulin (SHBG).54 This is a critical finding because when testosterone is bound to SHBG, it is essentially useless.

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Thus, magnesium seems to help “free” more testosterone, which can then be used by the cells of the body.

Like magnesium, zinc is an essential mineral that is involved in hundreds of metabolic reactions in the body. Researchers from Wayne State University in Detroit found that, among a sample of 40 healthy men, testosterone levels were significantly correlated to zinc concentrations. What’s more, the researchers found that when they deprived the men of zinc, their testosterone levels plummeted, and when men who were marginally deficient supplemented with zinc for 6 months, their testosterone levels significantly increased.55

Zinc appears to be closely correlated with testosterone levels, although there doesn’t appear to be any additional increase in testosterone if one is already consuming enough zinc. With that being said, it’s very much worth pointing out that zinc is one of the most common nutrient deficiencies. What’s more, both chronic and excessive exercise can lead to zinc deficiency, which has been found to be higher in both athletes and recreational exercisers.56–58 With all of that in mind, it’s important to make sure that one is consuming adequate amounts of zinc (through food and/or supplemental sources) to optimize testosterone levels.

Additionally, selenium may also play an important role in regulating testosterone levels. In one study published in the Journal of Urology, researchers from Iran found that men supplementing with selenium daily for 26 weeks significantly increased testosterone levels and improved semen quality.59 As you’ll see in just a moment, dietary sources of selenium may be even more prolific at increasing blood levels of this key micronutrient.

Exercise can be a potent stimulator of sex hormones like testosterone. In general, resistance training (especially programs that are high-volume and moderate- to high-intensity) and high-intensity interval training seem to have a beneficial impact on testosterone.60,61 On the contrary, prolonged aerobic exercise (i.e., steady-state endurance exercise) can result in significant decreases in testosterone that may last for days, and endurance athletes who engage in steady-state aerobic training on a regular basis may be at risk for chronic low levels of testosterone.61,62

When it comes to exercise, it’s important to note that more is not necessarily better;

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overtraining—both excessive exercise of any kind—has been shown to lead to decreases in testosterone and increases in the stress hormone cortisol.63

Speaking of stress, cortisol can have a negative impact on sex hormones, including testosterone. As Naturopathic Urologist Dr. Geo Espinosa says, “The fact of the matter is that cortisol castrates.”64

During times of stress, the body can literally “steal” the raw materials that are required for building sex hormones, like testosterone and estrogen, in order to increase production of cortisol. This explains, at least in part, why stress and increased cortisol typically have a negative (i.e., lowering) effect on circulating levels of testosterone.65

Generally speaking, there’s an inverse relationship between cortisol and testosterone. Fundamentally, this makes sense, as cortisol is a “catabolic” hormone (i.e., involved in “break down” processes) whereas testosterone is an “anabolic” hormone (i.e., involved in “building” processes).

As you may have experienced, stress can put a huge damper on your sex drive and libido, both directly (through hormonal changes) and indirectly (i.e., leaving you distracted). In fact, the physiological response to stress has been shown to inhibit the sexual response. In one study published in The Journal of Sexual Medicine, researchers from the University of Texas found that when women watched an erotic film, those who showed an increase in cortisol levels expressed significantly lower levels of arousal and sexual desire.66

Oxytocin appears to work counter to stress hormones, including cortisol. As mentioned before, massage both increases oxytocin and decreases levels of stress hormones.18

What’s more, a number of studies have shown that administration of oxytocin can reduce levels of the stress hormone cortisol and lower social anxiety.67,68

What does all of this mean? When you or your partner are feeling stressed, consider some of the ways that you may be able to facilitate oxytocin release, as it seems to have bountiful anti-stress effects.

When it comes to female hormones, as you might imagine, things can be a little complex. However, most women have a fairly regular, somewhat predictable menstrual

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cycle that provides some insight into when their sexual desire may be at its peak.

In general, a woman’s libido spikes around the time that she’s fertile (i.e., ovulating), which makes a great deal of sense. The ovulation window is typically about halfway between menstrual cycles for most women. In one study, researchers from the University of Virginia assessed the sexual functioning and libido of 115 women over the course of their menstrual cycle, and they found that the women reported more interest in sex and greater sexual satisfaction midcycle compared to other phases of their menstrual cycle.69

What’s more, researchers have found other signs of increased sexual desire and libido in women closer to ovulation than other periods. For instance, one study showed that women demonstrated higher blood flow and physiological arousal around the time of ovulation.70 Meanwhile, researchers at Arizona State University found that women reported greater instances of masturbation around ovulation.71

Interestingly, men seem to have an innate ability to “pick up” on the cyclical changes in a woman’s hormones and libido. In a study published in the journal Archives of Sexual Behavior, researchers from Canada videotaped 19 women as they walked down a street during ovulation and menstruation. Thirty-five men viewed the videos and rated the women’s sexual attractiveness. Compared with the menstrual women, the ovulating group swayed their hips more, and the men rated them sexier.72

For women, estrogen tends to peak just before ovulation. In a recent study published in the journal Hormones and Behavior, researchers from UC Santa Barbara found that a women’s sexual desire closely corresponds to when her estrogen levels peak.73

According to the study’s lead author James Roney, “We found two hormonal signals that had opposite effects on sexual motivation. Estrogen was having a positive effect. Progesterone was having a persistent negative effect, both for current day, day before, and two days earlier.” In other words, the researchers found while that estrogen increases a women’s libido, whereas progesterone (which peaks after ovulation in the second half of a women’s menstrual cycle) seems to act as a “stop sign.”

Along those lines, it may not come as too much of a surprise that once women reach menopause, which is characterized by reduced levels of estrogen, they typically

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experience reduced sex drive.74 Whether these changes are fully mediating by fluctuations in hormones is not entirely clear; however, research does suggest that a women’s level of sexual functioning declines after menopausal transition.

In addition to hormones, sexual desire and behavior can also be mediated by brain chemicals (i.e., neurotransmitters) such as dopamine and serotonin. Generally speaking, dopamine is considered to be the major neurotransmitter of sexual arousal. Low sexual desire is often considered to be a function of low levels of dopamine and reduced dopamine activity. Norepinephrine is another stimulatory neurotransmitter that is strongly linked to sexual arousal. Similarly, melanocortins, which are neuropeptides, are also linked to sexual arousal.75,76

Conversely, serotonin, which is often referred to as a “feel-good” neurotransmitter or “happy hormone” (although it’s not technically a hormone), acts an inhibitory neurotransmitter when it comes to sex. Increases in serotonin signal to the body a sense of “satiety,” or satisfaction. In fact, serotonin is released in large amounts after orgasm. This explains, at least in part, why folks who take selective serotonin reuptake inhibitors (SSRIs) often experience sexual dysfunction and reduced sexual desire.75,76

Before moving on, it’s important to point out that the bedroom is not just for love making. Make sure you get plenty of sleep while you’re there too, as this is the “magic” time when the body creates and releases many of its all-important sex chemicals.77 Not getting enough sleep can have a detrimental impact on your hormonal health. In fact, according to research published in the aptly-named journal Sleep, total sleep time predicts morning levels of testosterone.78 In other words, more sleep equals higher testosterone levels.

What’s more, in a study published in the prestigious Journal of the American Medical Association, researchers from the University of Chicago found that men who slept less than five hours a night for just ONE week had significantly lower levels of testosterone compared to when they had a full night’s sleep. Restricted sleep resulted in a whopping 15% reduction in testosterone levels!79

Speaking of sleep, in a recent study published in the Journal of Urology, Korean researchers found that nocturia (i.e., night-time peeing) is associated with low testosterone levels among a very large sample of men, and they found that this

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association was independent of age or prostate size, which are two factors that are often associated with nocturia. With that in mind, if you (or your partner) are waking up frequently during the night to pee, this could potentially be an indicator of low testosterone.80

As previously mentioned, sexual health is one of numerous components of the matrix that is your overall health. Put differently, sex is one of the many spokes of your “life web,” and while there are numerous spokes in the web, they are each connected and interrelated. For example, metabolic health and body composition can have a dramatic impact on sexual function and performance.

In fact, researchers have found high prevalence of erectile dysfunction (ED) in men who have metabolic syndrome (e.g., central obesity, insulin resistance/high blood sugar, hypertension, high triglycerides, low “good” cholesterol).81 Moreover, researchers recently found that insulin resistance may directly impact erectile function, as it is an independent determinant of ED.82

On the topic of metabolic syndrome, it’s evident that certain modifiable lifestyle factors (e.g., overweight/obesity, physical inactivity, a high-carbohydrate diet, cigarette smoking) play a significant role in its etiology. In turn, because these lifestyle factors are modifiable, researchers posit that “Modification of lifestyle factors, even later in life, has considerable potential for primary prevention of the metabolic syndrome.”83

In fact, additional studies have found that the risk of having metabolic syndrome is substantially lower in individuals who are physically active, nonsmoking, have a relatively low carbohydrate intake and moderate alcohol consumption, and who maintain a body mass index in the non-obese range.84

Thus, it’s important to consider each of the various domains and sub-domains that make up your life web, including relationships, health & function, work & hobbies, and personal growth. Each of these has the potential to impact the other, and ultimately, your sex life.

What all of that in mind, let’s dig into some of the best foods for better sex!

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1. Avocados

The avocado initially earned its reputation as an aphrodisiac (foods or compounds that are thought to enhance sexuality via increased sex drive) from the ancient Aztecs, which named the fruit ahuacate, the Aztec word for testicle. While the jury is still out on whether or not avocados really boost libido, they are an excellent source of monounsaturated fats, which, as pointed out previously, appear to be closely correlated to levels of important sex hormones. What’s more, avocados are also a very good source of vitamins E and B6, as well as potassium, which promote cardiovascular health and better blood flow.

2. Brazil Nuts

Brazil nuts are a fantastic source of selenium, which, as previously mentioned, has been shown to boost testosterone, improve sperm quality, and is even advocated for male infertility.59 Even more, studies have shown that Brazil nuts are more effective than supplements at raising blood levels of selenium.85

Selenium is an essential element for normal testicular development, production of sperm, and sperm motility and function. In one study published in the International Journal of General Medicine, researchers gave 690 infertile men a supplement that provided a combination of selenium (200 µg/day) and vitamin E (400 IU/day) for at least 100 days. Over 50% of the men demonstrated improved sperm motility and quality, and what’s more, 11% of the previously infertile men were successfully able to impregnate their partners during the trial!86

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3. Pumpkin Seeds

Pumpkin seeds are a very good source of magnesium and a good source of zinc, and as mentioned previously, these minerals play important roles in optimizing the production of sex hormones like testosterone. Not only that, pumpkin seeds contain phytosterols that may support prostate health.

In one double-blind, placebo-controlled study published in the journal Nutrition Research and Practice, researchers found that men with an enlarged prostate (i.e., benign prostatic hyperplasia, BPH) who took a pumpkin seed oil supplement experienced significant improvements in quality of life, prostate symptom scores, and maximal urinary flow in as little as 3 months of supplementation.87

This is worth noting because studies have also shown that BPH can negatively affect sexual functioning and other aspects of quality of life, and to compound matters, common treatments for BPH may result in sexual dysfunction. In general, men with BPH who have higher levels of lower urinary tract symptoms often experience erectile dysfunction, ejaculatory problems, lower libido, difficulty maintaining erections, and lower levels of sexual satisfaction.88

4. Dark Chocolate

Dark chocolate may help “set the mood” a number of ways, starting with its sensual taste and aroma. As you bite into chocolate, your body begins to release “feel good” endorphins, “the love hormone” oxytocin, and key neurotransmitters that increase arousal.

Dark chocolate contains a compound called phenethylamine, which is often called the “love drug,” as it promotes sexual desire and sex drive. Phenethylamine precipitates a release of dopamine, which is associated with reward and pleasure. What’s more,

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dopamine is among the most extensively studied neurotransmitter involved in the control of sexual behavior and arousal.89,90

In addition, a recent study in the journal Circulation found that the flavonoids in dark chocolate help improve circulation and blood flow.91 This is worth noting because both men and women alike rely on adequate blood flow for optimal sexual stimulation and performance.

5. Beets

Speaking of blood flow, beets—and in particular, beetroot juice—are a rich source of naturally-occurring nitrates, compounds that can increase the body’s production of nitric oxide, which is a potent vasodilator. More simply put, nitrates help “open up” the diameter of blood vessels and increase blood flow.

Nitrates from beets may even help lower blood pressure. In a series of studies published in the journal Hypertension, a group of researchers from The Barts and The London School of Medicine found that daily consumption of beetroot juice for 4 weeks resulted in significant improvements in blood pressure.92,93 Additionally, research has shown that beetroot juice may improve exercise and athletic performance by increasing time to exhaustion, improving power output, reducing perceived level of exertion (i.e., how hard activity feels), and increasing exercise tolerance.94–96

What about performance in the bedroom? Unfortunately, there haven’t been any randomized control trials that have looked at whether beets or beetroot juice can help improve sexual performance or function. However, in theory, it seems like it may provide some potential benefit, especially given that most pharmacological efforts to improve sexual performance rely on relaxing blood vessels and increasing blood flow to the genitalia.

In addition to beets, celery and cabbage also contain high concentrations of nitrates.

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6. Cranberries

Cranberries contain high concentrations of D-Mannose, a sugar that is also found naturally in other fruits like peaches, apples, and certain other berries (e.g., blueberries). D-Mannose plays an important role in human metabolism, and one of its very unique and prominent functions is its ability to inhibit bacteria (E. coli) from adhering to the tissue lining the urinary tract.97 This “bacteria-blocking” capability holds promise for preventing urinary tract infections (UTI).

In one study in the World Journal of Urology, researchers from Croatia set out to test whether D-Mannose supplementation would be effective for recurrent UTI prevention compared to a standard antibiotic treatment or placebo. 308 women with a history of recurrent UTI either took D-Mannose (2g/day), an antibiotic, or nothing (i.e., placebo) for 6 months. At the end of the study, only 14.6% of the women taking D-Mannose experienced recurrent UTI whereas 20.4% and 60.8% of the women taking the antibiotic and placebo, respectively, experienced recurrent UTI.98

This finding demonstrates that D-Mannose may be an effective and safe (with virtually no side effects) alternative to prevent recurrent UTI. This is important for a number of reasons. First, it is estimated that between 40 – 50% of women experience UTI at some point during their lives, and sex (especially more frequent sex and/or sex with multiple or new partners) may be one of the causes of UTI through the introduction of bacteria.99–101 On the other hand, if you’ve ever had a UTI, then you know that having sex can be painful, and generally speaking, doctors typically recommend abstaining from sex until the UTI is clear.

While UTI are generally uncommon in men under the age of 50, there is strong evidence linking erectile dysfunction to lower urinary tract symptoms (LUTS) in men, and UTI may complicate LUTS, leading to sexual dysfunction.102

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7. Oysters

Oysters are one of the most well-known aphrodisiacs and for good reason. They are a great source of zinc, which is essential for both male and female sex hormone production. Deficiencies in zinc can lead to delayed sexual development and lower sperm counts and testosterone in men. Oysters also contain two unique amino acids (including D-aspartic acid) that increase the production of sex hormones in both men and women.103

To get the benefit from oysters, it’s recommended to eat them raw, as cooking reduces the quantity of the amino acids responsible for boosting the sex chemicals.

8. Cruciferous vegetables

One unique benefit of cruciferous vegetables (a family of vegetables, including broccoli, cauliflower, arugula, cabbage, kale, and Brussels sprouts) is their ability to help promote healthy estrogen metabolism through a special phytonutrient called indole-3-carbinol (I3C).104 I3C helps promote an increase in the ratio of “good” (2-hydroxy estrogen) to “bad” estrogen (16-hydroxy estrogen). The “good” 2-hydroxy estrogen is a less active form that is typically excreted from the body more rapidly.

In one study, researchers from the University of Massachusetts, found that cruciferous vegetable consumption was associated with a significant increase in “good” to “bad” estrogen (i.e., 2:16-hydroxyesterone ratio). In fact, just a 10-gram-per-day increase in cruciferous vegetable intake was enough to improve the 2:16-hydroxyesterone ratio.105

A number of additional studies have demonstrated that either daily supplementation with I3C or the addition of broccoli (e.g., 2 cups per day) to one’s diet significantly improves the 2:16-hydroxyesterone ratio, which appears to be closely correlated to maintaining optimal female and overall health.106–108

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Not only that, through its beneficial effects on estrogen metabolism, I3C can help fight off dietary and environmental estrogens to which you may be exposed to through soy, plastics, personal care products, pesticides, and more. Environmental estrogens have been linked to reproductive issues and complications (e.g., infertility, endometriosis, reduced testosterone production), not to mention excess body fat, which itself releases estrogen.109–113 Thus, by consuming more cruciferous vegetables you’ll be fighting off unattractive belly fat stores at the same time as promoting a healthy hormonal environment.114

9. Eggs

Eggs are loaded with hormone-optimizing nutrients. For starters, eggs are a great source of fat, saturated fat, and cholesterol, all of which are associated with optimal levels of important sex hormones. What’s more, eggs are one of the very rare foods that are a good source of vitamin D.

Perhaps you’re concerned about the cholesterol content of eggs. Let’s talk about that for a moment. First off, the hormones often referred to as “sex hormones,” including testosterone, estrogen, and progesterone, technically are classified as “steroid hormones” due to their chemical structure.

Cholesterol—yes, that supposedly nasty “C-word”—is THE fundamental “building block” for the steroid hormones. The process of “steroidogenesis” (i.e., creation of steroid hormones) literally means the conversion of cholesterol to biologically active steroid hormones.115 Thus, without adequate cholesterol, levels of sex hormones plummet.

With that in mind, it may not come as too much of a surprise to learn that statins, drugs designed to reduce the body’s production of cholesterol, have been shown to consistently and significantly lower levels of sex hormones (including testosterone) in both men and women.116–118 Although there is some inconsistency among the evidence, some studies have associated statins with sexual dysfunction, including erectile dysfunction and decreased libido in men.119,120

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Beyond that, there’s the concern that dietary cholesterol leads to increased levels of blood cholesterol (more appropriately, the lipoproteins LDL and HDL that carry cholesterol) and an increased risk of heart disease. This is more commonly referred to as the “lipid hypothesis,” which has been called into question, picked apart, and largely discredited in recent years.121,122

In a cross-over study published in the International Journal of Cardiology, researchers from Yale Prevention Research Center assessed the effects of egg consumption on endothelial function (FMD), a reliable index of cardiovascular risk. 49 healthy men and women consumed two eggs per day for 6 weeks. At the end of the study, the researchers found that daily egg consumption did not affect total cholesterol, LDL, or FMD, providing clear evidence “that dietary cholesterol may be less detrimental to cardiovascular health than previously thought.”123

In one study published in the journal Nutrients, researchers from Wayne State University found that students who ate eggs for breakfast (providing 400mg of cholesterol) 5 days per week for 14 weeks experienced no negative impact on blood lipids (e.g., total cholesterol, LDL).124

In general, observational studies have not found a connection between egg consumption and risk of cardiovascular disease in otherwise healthy individuals. In a study published in the Journal of the American Medical Association, researchers from Harvard University’s Department of Nutrition assessed whether there was any connection between egg consumption and coronary heart disease (CHD) among over 117,000 otherwise healthy men and women over the course of 14 – 18 years. The researchers found “no evidence of an overall significant association between egg consumption and risk of CHD or stroke in either men or women.”125

In a study published in the journal Medical Science Monitor, researchers assessed the dietary patterns of nearly 10,000 adults (aged 25 – 74) to examine the association between egg consumption and risk of cardiovascular disease. They found that consumption of more than 6 eggs per week (average of at least 1 egg per day) does NOT increase the risk of stroke or cardiovascular disease.126

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In a recent study published in the European Journal of Clinical Nutrition, researchers from Spain set out to assess whether there was any connection between egg consumption and the risk of cardiovascular disease (CVD) among over 14,000 men and women (ages 20 – 90) who followed a Mediterranean-style diet. Once again, the researchers found no association between egg consumption and CVD risk when comparing folks with the highest to lowest egg consumption.127

Perhaps most interesting are the results from a study recently published in the journal Metabolism where researchers from the University of Connecticut compared the effects of eating 3 whole eggs per day versus an equivalent amount of yolk-free egg substitutes on blood lipids and insulin sensitivity. After 12 weeks, the researchers found that the participants who ate the whole eggs experienced significantly greater increases in HDL cholesterol and large HDL particles (i.e., the “good” forms of cholesterol), as well as reductions in total VLDL and medium VLDL particles. What’s more, the egg eaters also experienced significant improvements in insulin sensitivity and increases in HDL and LDL particle size (i.e., more large, fluffy particles).128 Particle size is noteworthy because small, dense particles are considered more detrimental than large, fluffy particles.129

Taken together, egg consumption does not seem to be a concern for otherwise healthy individuals, although this may be an issue for “hyper-responders” and diseased populations.130,131

There’s one more benefit to eggs worth mentioning. Like chocolate, eggs are thought to promote an increase in the “love hormone” oxytocin.

10. Beef

Beef is a very good source of zinc, and beef is also a good source of fat, of which about 40 – 50% is saturated fat and about 40 – 50% monounsaturated fat. As previously mentioned, total fat, saturated fat, and monounsaturated fat are all positively associated with the all-important sex hormone testosterone.

Women, take note; not only does zinc help promote healthy levels of testosterone,

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which you already know is an important sex chemical for you, it also curbs production of the hormone prolactin, which can impair sexual function. It’s normal for both men and women to release prolactin after sex; however, this initiates a negative feedback loop that decreases arousal.132,133

11. Coffee

Surprised to see this on the list? Acutely, caffeine can act as a vasoconstrictor (restricting blood flow), and if you’re sensitive to caffeine, it may leave you with an upset stomach and feelings of stress and anxiety, which can impair performance between the sheets. So, it may not be the beverage of choice immediately before sex.

However, in a recent study published in the journal PLOS ONE, researchers from the University of Texas found that men who drink 2 – 3 cups of coffee per day are less likely to experience erectile dysfunction.134

In conclusion, the World Health Organization defines sexual health as “a state of physical, emotional, mental and social well-being in relation to sexuality; it is not merely the absence of disease, dysfunction or infirmity. Sexual health requires a positive and respectful approach to sexuality and sexual relationships, as well as the possibility of having pleasurable and safe sexual experiences, free of coercion, discrimination and violence. For sexual health to be attained and maintained, the sexual rights of all persons must be respected, protected and fulfilled.”135

In other words, sex is complicated, and there are many factors that have the potential to influence sexual health, sexuality, sexual performance, and sexual desire. One of those factors, which also has an impact on many other areas of your life web, is your food choices, and we hope that you’ve found this guide to be a helpful start to improving your nutrition to optimize both sexual and overall health.

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