76 PRACTICAL DIABETES VOL. 31 NO. 2 COPYRIGHT © 2014 JOHN WILEY & SONS

BackgroundBefore the discovery of insulin andmodern drugs, carbohydrate (notjust sugar) restriction was the onlyrealistic treatment for all diabetes.1More recently, the drive has beenfor a low fat and therefore highercarbohydrate diet for all. It is inter-esting to note that despite theplethora of ‘low fat’ and ‘diet’ foodson the supermarket shelves, the epidemic of central obesity and diabetes (diabesity) continues toincrease across the developedworld. After years of demonising fatssome researchers are starting tolook at carbohydrate as a cause ofcentral obesity and diabetes.2,3 In2012, Emily Hu et al. showed a lineardose-relationship between rice con-sumption and risk of type 2 diabetesin a study involving more than350 000 subjects.4

The authors’ interest was firstsparked by the fact that even whole-meal bread (GI index 71) or baked

potato (GI index 85) has a higherglycaemic index than table sugaritself (GI index 68).5 Dr John Briffain his excellent book ‘Escape thediet trap’6 makes the point that,while fats contain the essential vita-mins A, D, E and K, carbohydraterepresents ‘empty calories’. So whyshould people with diabetes take inthe ‘concentrated sugar’ that is instarchy foods such as bread, pasta orrice at all?

Studies have shown good resultsfor a low carbohydrate/higher fatdiet in people with type 2 diabetesand in those with central obesity.2,3,7

However, the approach is generallyfrowned upon in the UK, despite thefact that many patients are trying it of their own accord. Googling ‘diabetes.co.uk forum low carb’, thelow carbohydrate success storieshave had over 81 000 views. In 2011,a detailed pathophysiological studyshowed that diet-induced weight lossbrought about falls in the fat content

Practice point

Low carbohydrate diet to achieve weight loss andimprove HbA1c in type 2 diabetes and pre-diabetes:experience from one general practice

AbstractPatients with diabetes have long been exhorted to give up sugar, encouraged instead to takein fuel as complex carbohydrate such as the starch found in bread, rice or pasta (especially if‘wholemeal’). However, bread has a higher glycaemic index than table sugar itself. There areno essential nutrients in starchy foods and people with diabetes struggle to deal with theglycaemic load they bring. The authors question why carbohydrate need form a major part ofthe diet at all. The central goal of achieving substantial weight loss has tended to beoverlooked. The current pilot study explores the results of a low carbohydrate diet for a caseseries of 19 type 2 diabetes and pre-diabetes patients over an eight-month period in asuburban general practice.

A low carbohydrate diet was observed to bring about major benefits. Blood glucosecontrol improved (HbA1c 51±14 to 40±4mmol/mol; p<0.001). By the end of the study periodonly two patients remained with an abnormal HbA1c (>42mmol/mol); even these two hadseen an average drop of 23.9mmol/mol. Weight fell from 100.2±16.4 to 91.0±17.1kg(p<0.0001), and waist circumference decreased from 120.2±9.6 to 105.6±11.5cm (p<0.0001).Simultaneously, blood pressure improved (systolic 148±17 to 133±15mmHg, p<0.005; anddiastolic 91±8 to 83±11mmHg, p<0.05). Serum gamma-glutamyltransferase decreased from75.2±54.7 to 40.6±29.2 U/L (p<0.005). Total serum cholesterol decreased from 5.5±1.0 to4.7±1.2mmol/L (p<0.01).

This approach is easy to implement in general practice, and brings rapid weight loss andimprovement in HbA1c. Copyright © 2014 John Wiley & Sons.

Practical Diabetes 2014; 31(2): 76–79

Key wordstype 2 diabetes; low carbohydrate diet; weight loss; primary care; diabesity; obesity; fatty liver;liver enzymes

Dr David UnwinFRCGP, Principal in General Practice, The NorwoodSurgery, Southport, UK

Dr Jen UnwinFBPsS, Consultant Clinical Psychologist, Southport &Ormskirk NHS Trust, UK

Correspondence to: Dr D Unwin, The Norwood Surgery, 11 Norwood Ave, Southport PR9 7EG, UK; email: david.unwin@GP-n84008.nhs.uk

Received: 8 November 2013 Accepted in revised form: 6 January 2014

of the liver and pancreas andreturned blood glucose control tonormal.8 In November 2013, aSwedish expert committee, SBU(Swedish Council on HealthTechnology Assessment), publishedtheir inquiry ‘Dietary Treatment for

Obesity’. According to SBU, the only clear difference among differ-ent dietary recommendations is seen during the first six months.Here a low carbohydrate diet ismore effective than today’s conven-tional advice.

We decided to trial the low carbo-hydrate weight loss diet in a suburbangeneral practice for patients with raised HbA1c (>42mmol/mol[6.0%]). In particular, we wonderedhow any weight loss would bematched by an improvement in othermeasured parameters such as HbA1cand blood pressure (BP). There wereearly concerns about the effect a dietwith more eggs and butter in it wouldhave on serum cholesterol levels. Thequestion of the acceptability of theapproach was central and so it wasdecided to provide group sessions forsupport and information sharing. We also wondered if group workcould help offset some of the costs ofthis approach.

MethodOver a couple of months theapproach was suggested opportunis-tically to patients with raised HbA1cduring routine GP or practice nurseappointments, or by approachingpeople on the impaired glucose tol-erance register of the practice. Theage range was 34–73 years. It wasimportant that the patients choosefreely if this was of interest. The dietsheet (Box 1) was handed out withthe repeated emphasis on ‘cut outsugar, bread, pasta, rice and pota-toes altogether’. Baseline measure-ments of weight, waist, BP, choles-terol, liver function, thyroid andrenal function were made. Thepatient was asked to make a second10-minute appointment if theywanted to take this further.

At the second appointment thediet sheet was discussed so thepatient could tailor the diet to theirlife. Patients appreciated that wetried very hard to help them under-stand how and why the diet couldhelp them achieve their goal ofweight loss and health gain. It wasfound to be better to spend moretime on this than being too prescrip-tive about the diet itself. No weigh-ing of food was required; patientswere reminded to ‘cut out the carbs’ while eating more vegetables,healthy fats and protein to avoidhunger. Patients were given a choiceof monthly 10-minute one-to-onereviews of progress or attending ourevening ‘Low Carb’ group meetings.About half opted for each. Allpatients were weighed at each review

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Low carbohydrate diet to achieve weight loss and improvements in HbA1c

Practice point

So what should I eat to control Diabetes or Pre-diabetes?

Reduce starchy carbs a lot (remember they are just concentrated sugar). If possible cut out the‘White Stuff’ like bread, pasta, rice – though porridge, new potatoes and oat cakes in moderationmay be fine. Sugar – cut it out altogether, although it will be in the blueberries, strawberries andraspberries you are allowed to eat freely. Cakes and biscuits are a mixture of sugar and starch thatmake it almost impossible to avoid food cravings; they just make you hungrier!!

All green veg/salads are fine – eat as much as you can. So that you still eat a good big dinner trysubstituting veg such as broccoli, courgettes or green beans for your mash, pasta or rice – stillcovering them with your gravy, bolognese or curry! Tip: try home-made soup – it can be taken towork for lunch and microwaved. Mushrooms, tomatoes, and onions can be included in this.

Fruit is trickier; some have too much sugar in and can set those carb cravings off. All berries aregreat and can be eaten freely; blueberries, raspberries, strawberries, apples and pears too, butnot tropical fruits like bananas, oranges, grapes, mangoes or pineapples.

Proteins such as in meat, eggs, fish – particularly oily fish such as salmon, mackerel or tuna –are fine and can be eaten freely. Plain full fat yoghurt makes a good breakfast with the berries.Processed meats such as bacon, ham, sausages or salami are not as healthy and should only beeaten in moderation.

Fats (yes, fats can be fine in moderation): olive oil is very useful, butter may be tastier thanmargarine and could be better for you! Coconut oil is great for stir fries. Four essential vitaminsA, D, E and K are only found in some fats or oils. Please avoid margarine, corn oil and vegetableoil. Beware ‘low fat’ foods. They often have sugar or sweeteners added to make them palatable.Full fat mayonnaise and pesto are definitely on!!

Cheese: only in moderation – it’s a very calorific mixture of fat, carbs and protein.

Snacks: avoid. But un-salted nuts such as almonds or walnuts are great to stave off hunger. Theoccasional treat of strong dark chocolate 70% or more in small quantity is allowed.

EATING LOTS OF VEG WITH PROTEIN AND FATS LEAVES YOU PROPERLY FULL in a way that lasts.

Finally, about sweeteners and what to drink – sweeteners have been proven to tease your braininto being even more hungry making weight loss almost impossible – drink tea, coffee, andwater or herb teas. I’m afraid alcoholic drinks are full of carbohydrate – for example, beer isalmost ‘liquid toast’ hence the beer belly!! Perhaps the odd glass of red wine wouldn’t be toobad if it doesn’t make you get hungry afterwards – or just plain water with a slice of lemon.

Where to get more info?

A book – ‘Escape the diet trap’ by Dr John Briffa (2013).6 Well researched and easy to read.

Internet – Google ‘about.com low carb diet’ for loads more info and recipes, or look into the closelyrelated PALEO DIET; also Google ‘diabetes.co.uk forum low carb’ for contact, recipes and hints.

BEFORE YOU START get an accurate weight and measure your waist, re-weigh and measureonce a week to see how you are doing and ask for help if problems or little progress is beingmade – GO ON DO IT!!!

Box 1. Advice sheet for patients

and usually had a BP check and waistmeasurement. Blood tests (HbA1c,cholesterol, liver function, renalfunction) were repeated on averageevery two months.

The emphasis at follow up wasreflecting upon what worked foreach patient and identifying per-sonal goals, while giving advice onhow to better tailor the diet to indi-vidual needs. It was notable that participants never lost their resultssheets and were keen to have the latest figures added on. We alsohanded out graphs of their progressto engage their families.

ResultsAll data are expressed as mean ± stan-dard deviation. A two-tailed pairedstudent’s t-test was used to comparedata before and after intervention.

Nineteen patients entered theprogramme with just one droppingout in the early stages (though therewas weight loss, the diet just didn’tsuit the individual). Of the 18 whopersisted with the diet, all had substantial weight loss. Initial weightfell from 100.2±16.4 to 91.0±17.1kg(mean weight loss 8.6±4.2kg;p<0.0001). Waist circumferencedecreased from 120.2±9.6 to105.6±11.5cm (p<0.0001).

Blood glucose control improvedsignificantly (HbA1c 51±14 to40±4mmol/mol; p<0.001). Only twopatients remained in the abnormalrange (>42mmol/mol); even thesetwo had seen an average drop of23.9mmol/mol. Simultaneously, BPimproved (systolic 148±17 to133±15mmHG, p<0.005; and dias-tolic 91±8 to 83±11mmHg, p<0.05).

Serum GGT (gamma-glutamyl-transferase) decreased from75.2±54.7 to 40.6±29.2 U/L(p<0.005). Total serum cholesteroldecreased from 5.5±1.0 to4.7±1.2mmol/L (p<0.01).

Seven patients were able to comeoff medication: metformin (onecompletely and two have halvedtheir dose), perindopril and lacidip-ine, as BP control improved so much. Additionally, metoclo-pramide, omeprazole and lanzopra-zole were discontinued, as symptomsof acid reflux improved.

Box 1 provides a case example.All 18 participants lost weight andhad improved HbA1c, and none had

higher cholesterol. The majorityreported improved energy and well-being, and many began exercising.

DiscussionIt was observed that a low carbohy-drate diet achieved substantialweight loss in all patients andbrought about normalisation ofblood glucose control in 16 out of18 patients. At the same time,plasma lipid profiles improved andBP fell allowing discontinuation ofantihypertensive therapy in someindividuals.

Patients were found to be mostmotivated to diet when they hadrecently been diagnosed with hyper-tension, diabetes or pre-diabetes. Wewonder if health professionals alwaysmake the most of this window ofopportunity to work together withour patients on weight reduction. Inthe past, the doctors on the teamsimply delegated this to the dieti-tians, whereas showing real interestcan demonstrate to our patients justhow central weight loss can be togood health.

The authors were struck by theenergy and enthusiasm as patientstook control of their lives instead ofwaiting patiently for doctors andnurses to ‘solve’ their problems. AsGPs we are more at home in chargeof one-to-one consultations, so thefirst group sessions were a bit daunt-ing. It helped to get into the habit offinding out what the patients’ besthopes or goals were and what wasgoing well so far. After a few meet-ings, members of the group were try-ing to help each other, often makingsensible suggestions.

Repeatedly, patients would stepon the scales expecting not to havelost weight, only to find that they

had lost several kilograms; they weresurprised by this as they had not felthungry on the low carbohydrate dietbut it had nevertheless worked. Forsome, carbohydrates appeared to beaddictive and increase appetite, sothat as they gave up carbohydratesthey felt much less hungry. Allpatients reported increases inenergy levels. An unexpected resultof the diet was that two of the part-ners, the practice manager, thedeputy practice manager and bothpractice nurses all went on the dietand remain on it.

The mechanistic basis of the normalisation of blood glucose con-trol after significant weight loss hasrecently been explained.8 Decreasein body fat brings about decrease inthe ectopic fat in both liver and pan-creas, and release from the fat-induced metabolic inhibition allowsresumption of normal function.9

An initial concern had been theeffect of increase in consumption of eggs and butter on serum cholesterol. The 15% improvementobserved raises interesting questionsabout the cholesterol dogma. Thesequestions have recently been wellaired elsewhere.10

The 47% improvement in serumGGT was another unexpected find-ing. The patients with the highestinitial levels seemed to improve themost, but on average there was adrop of approximately 35 U/L. Foryears, patients with raised GGTs hadtold us they didn’t drink alcohol.Now that the role of carbohydrate inexcess of requirements, especiallythe fructose component, is betterunderstood in the genesis of fattyliver, it is clear that excess carbohy-drates can be a cause of fatty liver.9,11

There are resource implicationsfor this. The average person withdiabetes required about 30 minutesof doctor or nurse time in the firstmonth, then about 15 minutes permonth. The groups run with about8–10 patients in each time and lastjust over an hour, so this helped ourefficiency. This level of support isnot needed indefinitely: after aboutfour months most can be ‘dis-charged’ to more routine follow up.Furthermore, this would be offset bypossible drug budget savings.

An important consideration is thelong-term outcomes of weight loss

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Low carbohydrate diet to achieve weight loss and improvements in HbA1c

Practice point

In April 2013, a 55-year-old patientpresented with tiredness, polydipsia andan HbA1c of 84mmol/mol. There wasmarked hepatomegaly; a fatty liver wasconfirmed on ultrasound scan, associatedwith deranged liver function tests (GGTwas 103 U/L). After three months on a lowcarbohydrate diet her liver was normal onultrasound, the HbA1c was down to41mmol/mol, and GGT was 12 U/L. Shereported feeling ‘great, 10 years younger’and has lost 17cm off her waist.

Box 1. A case example

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Low carbohydrate diet to achieve weight loss and improvements in HbA1c

Practice point

achieved with a low carbohydratediet. This was investigated in a small study by Nielsen andJoenssen.12 Sixteen people who lostweight on a low carbohydrate diet,from 100.6±4.7 to 89.2±4.3kg, with-out close follow up were 93.1±14.5kgafter 44 months.12 This studyobserved initial HbA1c was 8.0±1.5%falling to 6.9±1.1% after 44 months.

A positive approach to achievingsubstantial weight loss in a suburbangeneral practice has brought aboutnormalisation of blood glucose con-trol in most patients who engagedwith this approach, and majorimprovements in serum cholesteroland liver enzymes in all. The clinicalbenefit is accompanied by possiblecost benefits, despite need forincreased time input.

Scientifically, this work repre-sents only a small series of cases; alsothere is no evidence yet that thefindings would generalise to otherpractices. However, even so, it offerssome hope that there could besomething an average practice team

might do to help this group ofpatients enjoy better health.

Conclusions Based on our work so far, we canunderstand the reasons for the inter-net enthusiasm for a low carbohy-drate diet; the majority of patientslose weight rapidly and fairly easily;predictably the HbA1c levels are notfar behind. Cholesterol levels, liverenzymes and BP levels all improved.This approach is simple to imple-ment and much appreciated by people with diabetes.

AcknowledgmentsWe are so grateful for the enthusias-tic collaboration of the patientsinvolved, and also for the support ofall practice staff and the partners ofThe Norwood Surgery.

Heather Crossley, RGN, did a lotof this work at the practice.

Dr Simon Tobin gave assistancewith some of the cases and helpededit this paper; his encouragementis much appreciated.

Roy Taylor, Professor of Medicineand Metabolism, Newcastle Uni -versity, provided helpful discussion,statistical advice and comment inthe writing of this paper.

Declarations of interestsThere are no conflicts of interestdeclared.

References 1. Westman EC, et al. Dietary treatment of diabetes

mellitus in the pre-insulin era (1914–1922).Perspect Biol Med 2006;49:77–83.

2. Volek JS, Feinman RD. Carbohydrate restrictionimproves the features of Metabolic Syndrome.Metabolic Syndrome may be defined by theresponse to carbohydrate restriction. Nutr Metab(Lond) 2005;2:31.

3. Nordmann AJ, et al. Effects of low carbohydratediet vs low fat diets on weight loss and cardiovas-cular risk factors: a meta-analysis of randomizedcontrolled trials. Arch Intern Med 2006;166:285–93. [Erratum in Arch Intern Med 2006;166:932.]

4. Hu EA, et al. White rice consumption and risk oftype 2 diabetes: meta-analysis and systematicreview: BMJ 2012;344:e1454.

5. Foster-Powell K, et al. International table ofglycemic index and glycemic load values. Am J ClinNutr 2002;76:5–56.

6. Briffa J. Escape The Diet Trap, 4th edn. London:Fourth Estate, 2013.

7. Accurso A, et al. Dietary carbohydrate restriction intype 2 diabetes mellitus and metabolic syndrome:time for a critical appraisal. Nutr Metab (Lond)2008;5:9.

8. Lim EL, et al. Reversal of type 2 diabetes:Normalisation of beta cell function in associationwith decreased pancreas and liver triacylglycerol.Diabetologia 2011;54:2506–14.

9. Taylor R. Type 2 diabetes: etiology and reversibility.Diabetes Care 2013;36:1047–55.

10. Malhotra A. Saturated fat is not the major issue.BMJ 2013:347:f6340.

11. Lustig RH. Fructose: It’s ‘Alcohol Without the Buzz’.Adv Nutr 2013;4:226–35.

12. Nielsen JV, Joensson EA. Low-carbohydrate diet intype 2 diabetes: stable improvement of bodyweightand glycemic control during 44 months follow-up.Nutr Metab (Lond) 2008;5:14.

● It could be said that starchy foods such as bread, pasta or rice are just concentrated sugar,and as such may represent a block to good diabetic control; even wholemeal bread has ahigher glycaemic index (71) than table sugar itself (GI index 68). This is the basis for thelow carbohydrate diet currently gaining popularity via the internet

● A low carbohydrate diet was trialled in a primary care setting for 19 diabetic or pre-diabetic patients, bringing about improvements in health markers over an eight-month period. Blood glucose control improved – HbA1c 51±14 to 40±4mmol/mol(p<0.001) – as did weight which fell from 100.2±16.4kg to 91.0±17.1kg (p<0.0001)

● Patients reported the diet was surprisingly easy to comply with and also noticed increasingenergy levels. Seven patients were able to come off medication of one form or another

Key points

Find out how non-diabetes drugs impact diabetes patients. Visit the Practical Diabetes website and click on drug notes

Drug notes

Aliskiren l Amlodipine l Bisoprolol l Bromocriptine l Bumetanide l Carbamazepine l Cilostazol l Clopidogrel l Colesevelam l Dabigatran lDarbepoetin alfa l Diazoxide l Digoxin l Dipyridamole l Domperidone l Doxazosin l Dronedarone l Duloxetine l Eplerenone l Erythromycinl Ezetimibe l Gabapentin l Indapamide l Ivabradine l Labetalol l Lidocaine l Lorcaserin l Losartan l Methyldopa l Metoclopramide l Nicorandill Nifedipine l Omacor l Orlistat l Prasugrel l Prolonged-release nicotinic acid l Quinine sulphate l Ramipril l Ranolazine l Rimonabant lRivaroxaban l Rosuvastatin l Sibutramine l Spironolactone l Tadalafil l Testosterone l Torcetrapib

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