There are sound theoretical reasons why a diet which is low in carbohydrates and high in certain fats fats is consistent with good health and longevity. This is supported by numerous case histories from individuals as well as long and short term studies. A useful contribution to our understanding has been provided by a recent study conducted in Australia under the auspices of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) (1). This investigation was specifically aimed at those with Type 2 diabetes (T2D) who were overweight or obese. The participants were divided into 2 matched groups. One of these was allocated to a diet containing 14% energy (<50 g/day) of carbohydrates (Low carb, LC) and other had a diet with 53% energy as carbohydrates (High carb, HC). All participants were required to undertake vigorous exercise under supervision on 3 occasions every week. The calorie intake in both groups was similar and the study continued for a full calendar year.
Both groups lost weight and also achieved similar reductions in the HbA1c (the % glucose attached to the haemoglobin which gives a good estimate of the blood glucose over the past 3 months) However in other respects the LC group was superior. In particular, it was found that there was less variation in the blood glucose levels over a 24-hour period, which meant that there were significant reductions in medication needed for glycaemic control. This is highly important because there would be considerable reductions in the costs of treatment coupled with less likelihood of drug-related side effects. These include hypoglycaemia, which is what happens if a drug reduces the blood glucose to levels which are too low, so that the patient loses consciousness.
In another paper written by members of the same research team it was noted that the total economic costs of T2D have been estimated as A$10.3 billion in Australia and US$174 billion in the USA (2). Referring to the results of the study described here, they comment:
“its most striking benefit is that it reduces the amount of medication someone with diabetes has to take by half. This reduction was three times greater than for people who followed the lifestyle program that incorporates a traditional high-carbohydrate diet plan”.
In 2008-2009, the cost of treating T2D in Australia was just over A$1,507 million of which one third was spent on medication. It is suggested that by helping patients with T2D to switch to an LC diet, there would also be enormous improvements in personal health and well-being.
Although the savings in expenditure on treatment are substantial they are relatively small when compared with the benefits to the national economy of reducing the number of people who suffer from T2D.
These results from the leading research body in Australia highlight the extraordinary position taken by the Dietitians Association of Australia (DAA) (3).In a statement on its website, apparently written in July 2015, it effectively endorses that of the Diabetes Australia organization which is that:
“very low carbohydrate diets are not recommended for people with diabetes. The organization states: ‘If you eat regular meals and spread your carbohydrate foods evenly throughout the day, you will help maintain your energy levels without causing large rises in your blood glucose levels’ ….. Diabetes Australia recommends people with diabetes eat moderate amounts of carbohydrate and include high-fibre foods that also have a low glycaemic index (GI)” (4).
It continues by emphasizing the importance of including carbohydrates in the diet:
“While there are specific requirements for amino acids (from proteins) in the diet, and essential fatty acids (from fats), there is talk that there is no specific requirement for carbohydrate.
This is not true. Both your brain and red blood cells require glucose and while some can be supplied by breaking down proteins in your body, there are a number of reasons why this is not beneficial and is specifically not recommended – for example, during childhood (due to growth requirements) and during pregnancy. The long-term effect of placing this demand on the body has also not been tested and there is evidence to suggest that performance in mental and physical tasks could be affected. Therefore, a diet that is very low in carbohydrate may not be physically or mentally sustainable as a diet pattern.
In addition, carbohydrate foods supply many nutrients. These include B vitamins and fibre from grains, and vitamins, minerals, dietary fibre and other plant components such as antioxidants from fruit and starchy vegetables. So without careful planning, it can be more difficult to meet nutrition needs on a low carbohydrate diet”.
The reality is that there is no specific requirement for carbohydrates by the human body. Here is a quote From Dr Walter Willett who is Chairman of the Department of Nutrition at the Harvard School of Public Health:
“One thing we know is that the grains are not essential for sure in a diet, but if we replaced them all with sugar that would be even worse, so that to make a point about relativity being important, but even carbohydrate in general is not essential as a nutrient. We have essential fats, we have essential proteins, amino acids and proteins, but grains and carbohydrate in general are not essential and it would be fine if people did replace all of the grain with a wide variety of vegetables, so that is good news, a wide variety of options that can be healthy, not just a single sort of exactly one style of diet.” (emphasis added)
The energy demand can be met effectively by fat. Any glucose which is needed can be produced in the body from protein and/or fat. There are examples of populations which such as Eskimos and the Maasai tribe in Africa which live on a diet which is high in fat and are perfectly healthy.
Not only does the DAA advise against a LC diet but it has recently expelled one its members Jen Elliott because of her recommendation to lower carbohydrate diets to people with insulin resistance and type 2 diabetes (T2D) (6). The complaint originated from another dietitian who did not agree with the approach taken by Jen who claimed that the recommendation of:
“a very low carbohydrate diet for type 2 diabetes management is inconsistent with Evidence Based Practice”.
Details are given in a previous blog (7).
It is abundantly clear that the DAA has adopted a stance that is untenable. The evidence from the CSIRO which is in agreement with that of many other investigations confirms that the advice being promulgated by the DAA is actually contributing to the growing incidence of T2D in Australia. Although the change to an LC diet would be an effective therapy, the DAA is aggressively opposed to this as demonstrated by the expulsion of Jen Elliott. We now learn that Health Minister in New South Wales has seen fit not to intervene on behalf of Jen.
The DAA and other bodies which take the same approach are definite contributors to the growing incidence of T2D which is causing unnecessary suffering, increasing expenditure on treatment and damaging to the economy. It is imperative for the Federal Government to step in and clean up this almighty mess. Jen Elliott has behaved impeccably and it is appalling that she has been treated so despicably. In fact she should be applauded for highlighting what is absolutely scandalous behaviour on the part of a professional body which seems to have completely lost sight of its fundamental purpose. This issue is not going to go away. Immediate action is needed and must include the exoneration of Jen Elliott.
- J Tay et al (2015) http://ajcn.nutrition.org/content/102/4/780.full.pdf
- C Proud et al (2015) https://theconversation.com/how-the-right-diet-can-control-diabetes-and-reduce-its-massive-economic-costs-42910