Diabetes: fighting it with a knife and fork
Introduction In the UK alone 2.8 million people are diagnosed with diabetes, while it is estimated that up to half a million more people have not as yet been diagnosed. With type 2 diabetes growing ever faster into epidemic proportions and general dietary advice and medication not achieving a substantial change, both healthcare professionals and the public should turn their attention to the diet that has been shown to be able to prevent and even reverse the disease or at least significantly reduce the need for medication.
What causes diabetes? Type 2 diabetes is usually, albeit not always, linked to increased body weight and especially to abdominal obesity. When the body's metabolism can't keep up with the amount and type of food eaten, droplets of fat are stored also in muscle cells as intramyocellular lipids (Petersen et al., 2004). When the amount of this fat reaches a certain level, it starts interfering with the cells' ability to react to insulin correctly. Studies show that these lipids start accumulating many years before type 2 diabetes manifests (Phillips et al.; 1996; Krssak et al., 1999; Petersen et al., 2004) and it has been confirmed that insulin resistance in muscles and liver is strongly linked to fat storage in these tissues (Delarue and Magnan, 2007; Morino et al., 2006).
Under normal conditions, fat is metabolised by the cells’ own powerhouses – mitochondria - but it appears that people with type 2 diabetes have fewer mitochondria in their cells than they need to successfully burn all the supplied fat. As a consequence, the fat accumulates inside the cells faster (Barnard, 2007).
However, as shown by another study (Sparks et al., 2005) where young healthy men were put on a special, high-fat diet that drew 50 per cent of its calories from fat – a diet not too different from that of many people in Western countries – accumulation of fat inside cells can be extremely fast even in perfectly healthy people.
What is the D-Diet and how does it work? It’s well known that a lifestyle intervention approach can yield remarkable results but there’s one diet in particular – the D-Diet – that can actually reverse the condition.
In one of the groundbreaking studies, researchers employed a combination of diet change and exercise (Barnard et al., 1994). The subjects were 197 men with type 2 diabetes and after just three weeks, 140 of them were able to discontinue their medication. Several studies followed (Barnard et al., 2006; Barnard et al., 2009a; Barnard et al., 2009b), each of them testing the effects of a plant-based, low-fat diet that emphasises foods with low glycemic index. All of them came to the same conclusion – that this type of diet is more effective than any other diet and even some medication.
The D-Diet- a low-fat wholesome vegan diet – not onlhy helps the body reduce the fat stores in the cells, which are causing insulin resistancy but it brings about improved blood sugar control, reduces blood cholesterol, helps to induce weight loss without portion restriction, prevents further kidney and nerve damage and helps to lower blood pressure.
The usefulness of vegan diet was eventually endorsed even by the American Diabetes Association when in 2010, their Clinical Practice Guidelines stated that plant-based diets had been shown to improve metabolic control in persons with diabetes (American Diabetes Association, 2010).
Basic principles of the D-Diet:
1st principle: no animal products
By eliminating all animal products diabetics avoid eating substantial amounts of fat and their cholesterol intake will be zero. Even lean, white meat and fish contain surprisingly high amounts of fat. For example, 38 per cent of calories from roast chicken and 40 per cent of calories from salmon come from fat (Food Standards Agency, 2002). Most of the fat found in animal products is saturated and there absolutely no requirement for saturated fats in our diet.
Reducing fat intake is vital for many reasons – in order to reduce the amount of intramyocellular lipid, which interferes with muscle cells’ insulin sensitivity, for cardiovascular health and for general weight loss.
This diet excludes all animal products also because animal protein from meat, fish, dairy or eggs places an additional strain on the kidneys and can increase the damage already caused by diabetes (Knight et al., 2003; Barclay et al., 2010). Protecting the kidneys is another key issue for diabetics.
All foods should be of plant origin and unrefined wherever possible, which means they will be naturally high in fibre and complex carbohydrates, and low in fat (except oils, nuts and seeds). Animal products contain no fibre or healthy carbohydrates while plant foods (supplemented with vitamin B12) contain all the essential nutrients we need.
2nd principle: low-fat
Even though vegetable oils are better for the body than animal fats because they contain essential fatty acids, less saturated fat and no cholesterol, it is important to keep them to a minimum. In order to reverse or improve the diabetic condition, it is essential to reduce intracellular fats (Barnard, 2007) but this can only happen if excessive fat consumption is avoided.
Low-fat vegan diet vs a conventional low-fat diet One of the pilot studies on the effects of a vegan diet showed that there are important differences between types of fat in a low-fat regime (Nicholson et al., 1999). Researchers compared the potential of a low-fat vegan diet with a conventional low-fat diet. Participants were all type 2 diabetics and they followed the assigned diet for 12 weeks. At the end of the study period, the vegan group had an impressive 28 per cent reduction in fasting plasma glucose levels. The reduction in the conventional group was only 12 per cent. The average weight loss was 7.2 kg in the vegan group compared to 3.8 in the conventional group. Medication was reduced in all vegan participants, in one of them completely, whilst there were no reductions in medication in the conventional group.
The amount of fat per serving should not exceed three grams (or ten per cent of calories from fat). Preferred types of oils should be those with high omega-3 content – flaxseed, hempseed and walnut for cold preparation and rapeseed for cooking. Apart from added oils, diabetics should also limit their consumption of nuts and seeds.
3rd principle: low glycemic index (GI)
Glycemic index, or GI, is a measure of the effects of carbohydrates on blood sugar levels. Carbohydrates that break down quickly during digestion and rapidly release glucose into the blood have a high GI. Carbohydrates that break down more slowly, releasing glucose gradually into the bloodstream, have a low GI.
To help the body deal effectively with the carbohydrate content of different foods, those that release their energy slowly should be preferred. Low GI means that after ingestion, blood glucose will not reach high levels, which is exactly what people with diabetes need. It allows them to better control their blood sugar and reduce the likelihood of complications caused by hyperglycemia, such as retinopathy, neuropathy and nephropathy (kidney disease) as well as hypoglycemia.
Glycemic index of selected foods (from Glycemic Index Database and The GI Diet Guide)
55 or less
Most fruits and vegetables, pulses (beans, soya, peas, lentils, chickpeas), barley, buckwheat, hummus, pasta, nuts and seeds, sweet potatoes, dried apricots and prunes, rolled oats, all-bran cereals, wholegrain pumpernickel bread, soya yoghurt and products low in carbohydrates
wholewheat bread, rye bread, crisp bread, brown rice, basmati rice, corn, porridge oats, shredded wheat, pineapple, cantaloupe melon, figs, raisins, beans in tomato sauce
70 and above
potatoes, watermelon, pumpkin, white bread, French baguette, white rice, rice cakes, corn flakes, processed breakfast cereals, dates, sugary foods
Results from 14 studies on glycemic index show that the benefit of low GI food consumption is similar to that offered by medication targeting postprandial hyperglycemia (Brand-Miller, 2003).
Summary The D-Diet should contain only foods from plant sources, a minimum of oils (low fat) and should be rich in foods with a low glycemic index (low GI). For these reasons, the D-Diet is based on whole grains, pulses, soya products, vegetables, fruit and nuts and seeds. Whilst limiting the types of food eaten, this diet does not limit the amount of food consumed. Being high in fibre and digested gradually, the recommended foods make the consumer feel full sooner and for longer, while calorie intake is reduced by the minimal amount of fat it contains (per volume of food eaten). Research shows that results in diabetics who follow a low-fat, wholefood, vegan diet are better than any single drug can produce (Barnard, 2007).
Vitamin B12 for all A vegan diet based on these principles is the healthiest possible, however, there is a need for vitamin B12 supplementation either in the form of food supplements or enriched foods, such as soya milk or margarines. This requirement is not solely vegan-specific as B12 supplementation is recommended for all people over the age of 50. B12 requirements may be also higher in diabetics as the commonly taken drug, Metformin, can reduce absorption of this vitamin (Diabetes UK, 2008).
Vegan and vegetarian diets: why they are so good The nutritional adequacy of a well-planned, vegetarian or vegan diet has been consistently confirmed. As the latest review concluded (Craig, 2010) – a vegetarian diet, including fortified foods, is nutritionally suitable for adults and children and promotes better health. The same review states that vegetarians have lower body weight, total and LDL (bad) cholesterol, blood pressure, reduced rates of deaths from heart disease; and decreased incidences of high blood pressure, stroke, type 2 diabetes and certain cancers.
Case studies Peter Scott, 55, who has been diabetic for several years says: "After being diagnosed, I became a typical example of metabolic syndrome – fat round the middle, high BMI, high cholesterol and high blood sugar. I had no energy, would cough a lot despite not smoking and didn't sleep well. But then I heard about the D-Diet and everything slowly began to change. After four weeks on the diet, my blood pressure started to fall towards normal levels. After a month, all my blood readings were approaching or within normal ranges. After eight weeks on the D-Diet I've lost 1 stone 7lb. I feel fitter, I sleep well, I wake up more quickly even without coffee and I've stopped the coughing probably because I stopped drinking milk," he says.
Another diabetic, Andrew Wedge, shares his experience: “It is just over 3 months since I stopped taking the metformin and pioglitazone medication. I have been for my HbA1c check this morning and the results indicated good control of the condition. As of today I am a little over a stone lighter than before I started the diet, the weight was lost during the four weeks and has stayed off.’
Conclusion As diabetes continues to spread worldwide, it is essential that an effective approach is adopted for its prevention and treatment.
If you want to know more about the science behind this campaign - including the relevance of the diet on type 1 (insulin dependent diabetics), read our fully referenced scientific report The Big D: defeating diabetes through diet and for more practical information including menu plans, recipes and cooking and shopping tips, see The D-Diet guide – both available to download for free or to order at Viva!Health or call 0117 970 5190.
Or why not order our unique D-pack and try the D-Diet for four weeks?
References: American Diabetes Association: Standards of medical care in diabetes – 2010. Diabetes Care. 33 (Suppl. 1) S11-S61
Barclay, A., Gilbertson, H., Marsh, K., Smart, C., 2010. Dietary management in diabetes. Australian Family Physician. 39 (8) 579-83
Barnard, R.J., Jung, T., Inkeles, S.B., 1994. Diet and exercise in the treatment of NIDDM: The need for early emphasis. Diabetes Care. 17 (12) 1469-72
Barnard N.D., Cohen J., Jenkins D.J., et al., 2006. A low-fat, vegan diet improves glycemic control and cardiovascular risk factors in a randomized clinical trial in individuals with type 2 diabetes. Diabetes Care. 29 (8) 1777-83
Barnard, N.D., 2007. Dr. Neal Barnard’s program for reversing diabetes: the scientifically proven system for reversing diabetes without drugs. USA, New York: Rodale Inc.
Barnard, N.D., Cohen, J., Jenkins, D.J.A., et al., 2009a. A low-fat vegan diet and conventional diabetes diet in the treatment of type 2 diabetes: a randomized, controlled, 74-wk clinical trial. American Journal of Clinical Nutrition. 89 (5) 1588S-96S
Barnard, N.D., Gloede, L., Cohen, J., et al., 2009b. A low-fat vegan diet elicits greater macronutrient changes, but is comparable in adherence and acceptability, compared with a more conventional diabetes diet among individuals with type 2 diabetes. Journal of the American Dietetic Association. 109 (2) 263-72
Brand-Miller, J., Petocz, P., Hayne, S., Colagiuri, S., 2003. Low–Glycemic Index Diets in the Management of Diabetes: a metaanalysis of randomized controlled trials. Diabetes Care. 26 (8) 2261-7
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Food Standards Agency (2002): McCance and Widdowson’s The Composition of Foods. Sixth summary edition.
Glycemic Index Database. [online] http://www.glycemicindex.com/
Knight, E.L., Stampfer, M.J., Hankinson, S.E., et al., 2003. The impact of protein intake on renal function decline in women with normal renal function or mild renal insufficiency. Annals of Internal Medicine. 138 (6) 460-7
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Petersen, K.F., Dufour. S., Befroy, D., et al., 2004. Impaired mitochondrial activity in the insulin-resistant offspring of patients with type 2 diabetes. New England Journal of Medicine. 350 (7) 664-71
Phillips D.I., Caddy S., Ilic V., et al., 1996. Intramuscular triglyceride and muscle insulin sensitivity: evidence for a relationship in nondiabetic subjects. Metabolism. 45 (8) 947–50
Sparks, L.M., Xie, H., Koza, R.A. et al., 2005. A high-fat diet coordinately downregulates genes required for mitochondrial oxidative phosphorylation in skeletal muscle. Diabetes. 54 (7) 1926-33
The GI Diet Guide. [online] http://www.the-gi-diet.org/lowgifoods/ Health Features home
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