Dietary Carbohydrates and Heart Disease

If we cut fats out of our diets, we have to eat something else to supply our bodies' energy needs. 'Healthy eating' decrees that this must be starchy carbohydrates and fruit and veg, which is more carbohydrates. But could these carbohydrates actually be a cause of the heart disease they are supposed to stop?

Dietary Carbohydrates and Heart Disease

In 2005 a study conducted at Johns Hopkins Bloomberg School of Public Health of diagnosed and undiagnosed diabetics showed clearly that high blood glucose levels were strongly associated with heart disease. The authors concluded that 'Chronically elevated glucose levels may contribute to the development of atherosclerosis in people with diabetes, independent of other risk factors.'[1] This points to 'healthy' carbohydrate being the culprit — not saturated fats.

It supports another strong indicator that carbohydrates are to blame. This came from a study of coeliac patients at the University of Nottingham. Coeliacs mustn't eat cereal grains. Although rates of heart attack and stroke were similar, adults with coeliac disease did have less hypertension and lower blood cholesterol compared with the general population.[2]

'Healthy eating' increases heart disease . . .

For over half a century we have been exhorted to eat less fat and to eat more carbohydrate-rich foods instead. A 'healthy diet' today is one low in fats and based on bread, pasta, rice and 'five portions of fruit and vegetables a day'. Here are some quotes from trials of our 'healthy diet', showing that canging to carbs might not be such a good idea:

In diabetics.
'In general, study has demonstrated that multiple risk factors for coronary heart disease are worsened for diabetics who consume the low-fat, high-carbohydrate diet so often recommended to reduce these risks.'[3] This is because high levels of glucose in the blood over a long period of time 'glycosylate' haemoglobin. This glycosylation was found to increase the risk of a heart attack in both diabetics and non-diabetics in a 2005 study by scientists at Johns Hopkins University.[4] In this study, non-diabetics' risk was more than doubled.

In older women.
'Low-fat, high-carbohydrate diets [15% protein, 60% carbohydrate, 25% fat] increase the risk of heart disease in post-menopausal women.'[5]

In the elderly.
All our cells rely on a constant and sufficient supply of cholesterol. There are two aspects of the advice aimed at lowering cholesterol which may have a profound effect on both our longevity and the efficiency with which our brains work. Firstly, we have known for a very long time that blood cholesterol levels tend to increase as we get older. Indeed several studies from around the world show that the elderly with high cholesterol live longer than those with low-cholesterol. Secondly, an East German doctor, Max Bürger, demonstrated almost half a century ago that, as we age, cholesterol is lost from body tissues and neurons (brain cells).[6] These findings were published in Leipzig during the Communist era, so it is unlikely that any Western clinician has ever seen, let alone read them. Putting these two facts together, is it not probable that the increases of blood cholesterol seen as we age are our bodies' way of replacing cholesterol lost from tissues and nerve cells?

This has huge implications in the context of 'healthy eating'. Advice today is aimed at lowering cholesterol levels in people of all ages, but these facts together suggest that drug or dietary regimes aimed at lowering cholesterol in people aged over seventy might well shorten their lives.

In everyone.
In 2000, scientists from Stanford University School of Medicine, California, compared the effects of a low-fat, high-carbohydrate diet with a high-fat, low-carbohydrate diet, on blood fats and cholesterol. They found that subjects on the high-carb diet had significantly higher blood triglycerides and significantly lower HDL. These effects are not desirable. The authors conclude:

'Given the atherogenic potential of these changes in lipoprotein metabolism, it seems appropriate to question the wisdom of recommending that all Americans should replace dietary saturated fat with [carbohydrate].'[7]

Similarly, while presenting two-year results of the Glucose Abnormalities in Patients with Myocardial Infarction (GAMI) study,[8] at the European Society of Cardiology Congress 2004, Dr Lars of the Rydén Karolinska University Hospital, Solna, Sweden, said that abnormal glucose metabolism is common in acute heart attack patients. 'We know that blood glucose increased to a level below the diagnostic target for diabetes increases the risk for mortality and cardiovascular disease.' He told delegates that patients' prognosis if they had normal glucose regulation was 'quite nice'; none in the normal group died. But amongst patients without any previously known diabetes newly detected a few days after a heart attack who had abnormal glucose tolerance 'there is a substantial increase in end points.'

Forget cholesterol; in this study abnormal glucose metabolism was the strongest predictor of a future heart attack. And that points to 'healthy eating' as a causal factor.

'Healthy' diets increase heart disease risk

Here is a curious fact which you can check with any veterinary surgeon: There are three basic types of animal when it comes to diet:

  • Herbivores which eat only plants,
  • Omnivores which eat both meat and plants,
  • Carnivores, which eat only meat.

While all three types can suffer a heart attack, the only animals where atherosclerosis builds up are those which eat plants, whether they eat plants exclusively or together with meat. And this includes Humans. This suggests that, contrary to popular wisdom, it is not something in meat that is the contributory factor, but something in plants.

In 2005, the medical Journal, Archives of Internal Medicine, published a study with showed clearly that when blood glucose levels were raised for significant lengths of time, the risk of a heart attack was greatly increased.[9]

Long-term blood glucose levels are measured by the amount they glycosylate haemoglobin. The measurement is known as 'HbA1c' or 'haemoglobin A1c'. What this study showed was that, in diabetic adults, each 1% increase in HbA1c increased the risk of a heart attack by 14%. And in non-diabetics with a level of over 4.6%, each 1% increase in HbA1c increased the risk of a heart attack by a huge 136%. Long-term high glucose levels are, of course, only caused by eating a 'healthy', carbohydrate-rich diet.


1. Selvin E, et al. Glycemic control, atherosclerosis, and risk factors for cardiovascular disease in individuals with diabetes: the atherosclerosis risk in communities study. Diabetes Care. 2005; 28: 1965-73.
2. West J, Logan RF, Card TR, Smith C, Hubbard R. Risk of vascular disease in adults with diagnosed coeliac disease: a population-based study. Aliment Pharmacol Ther 2004; 20: 73-9.
3. Chen YD, et al. Why do low-fat, high-carbohydrate diets accentuate postprandial lipemia in patients with NIDDM? Diabetes Care 1995; 18: 10-16.
4. Selvin E, et al. Glycemic control and coronary heart disease risk in persons with and without diabetes: the atherosclerosis risk in communities study. Arch Intern Med. 2005; 165: 1910-6.
5. Jeppeson J, et al. Effects of low-fat, high-carbohydrate diets on risk factors for ischemic heart disease in postmenopausal women. Am J Clin Nutr 1997; 65: 1027-33.
6. Max Bürger. Altern und Krankheit als Problem der Biomorphose. 3rd Ed, Georg Thieme, Leipzig, 1957.
7. Abbasi F, et al. High carbohydrate diets, triglyceride-rich lipoproteins and coronary heart disease risk. Am J Cardiol 2000; 85: 45-48
8. Norhammar A, et al. Glucose metabolism in patients with acute myocardial infarction and no previous diagnosis of diabetes mellitus: a prospective study. Lancet 2002; 359: 2140-4.
9. Selvin E, et al. op cit.

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Last updated: December 9, 2011