Tuesday, 22 March 2016 05:06

The truth behind the "blood sugar diet"

The truth behind Michael Mosleys’ “the blood sugar diet” by Lauren Jones (APD, AN)

 Lauren Profile

Michael Mosley was recently interviewed on SBS about his new blood sugar diet for the “reversal” of type 2 diabetes. Mosley claims that an 8 week 800 calorie diet followed by a Mediterranean style diet with low intake of carbohydrates will reverse diabetes, he is also of the opinion that the “low fat diet” currently recommended by health care professionals and Diabetes Australia is out dated and that there is no need to limit dietary intake of fat when sugar is the real underlying problem. Unfortunately there were no Dietitians interviewed on this topic during the program so here is a summary of what was not covered (and should have been!)

Points made by Michael Moseley, are they true or false?


1. The 8 week 800 calorie diet will reverse diabetes and improve blood sugar level

True. Any diet which restricts calorie intake to less than a persons daily calorie requirement will result in weight loss, this is due to the energy deficit created when energy out (expended in exercise and metabolic function) exceeds energy in (through diet).  Any diet that restricts calories and causes weight loss will improve the complications of diabetes however there is still much debate over whether diabetes can be reversed.  A very low calorie diet such as this is not recommended long term as it can induce the “starvation effect” where the body begins to preserve energy (stores fat) at times where calorie intake is insufficient to meet requirements. This protective mechanism paired with the difficulties of sticking to a diet this low in calories reduces the capability of long term healthy diet maintenance with many people eventually gaining all the weight they had originally lost once they return to their normal eating habits.  


2. The blood sugar diet is similar to the Mediterranean diet

False. The traditional Mediterranean diet is not a low carbohydrate diet. It is in fact moderate with regard to carbohydrate composition and recommends approximately 1-2 serves of breads/cereals/grains per main meal.  The Mediterranean diet also encourages choosing low fat dairy products whereas Mosley rejects this idea claiming that it is dated. 


3. Carbohydrates should be avoided as they will all cause rapid effects on blood sugar levels

False. Carbohydrates are a great source of energy, fibre and micronutrients and should not be cut out of the diet. Instead carbohydrates should be eaten in moderation, with low GI options chosen where possible.  Mosley did not differentiate between refined sugar and whole complex unprocessed carbohydrates (eg. Wholegrains) which are low GI and have less of an effect on blood sugar levels- he simply classified “majority” of carbohydrate rich foods as “bad”.


4. All low fat products should be avoided because they have more added sugar or other things added in processing to make them taste better.

False. Yes it is true that SOME products (eg. Yoghurts) may have added sugar, whether it is extra fruit or simply extra sugar to enhance the flavor, but this is not true for ALL products. For example, skim milk is lower in total fat than full cream milk but does not have any extra sugar added to it, it is simply an extra processing step involved in skimming the fat off of the milk. This becomes obvious when you familiarize yourself with nutrient content information on food packages. Throughout the program there was no mention of the different types of fats (saturated, monounsaturated or polyunsaturated fats) and the effects they have in the body. Saturated fats commonly found in processed foods and animal products (meat and dairy) cause an increase in cholesterol levels, whilst unsaturated fats (commonly found in plant based sources and fish) act to reduce cholesterol levels. The current evidence based recommendations support a diet low in saturated fat but including small amounts of foods rich in mono and polyunsaturated fats. 


Although some of the theories behind Michael Mosleys’ blood sugar diet are supported by scientific evidence, it is important that you have all the facts before making a lifestyle change. The current dietary recommendations for type 2 diabetics are evidence based and supported by the Dietitians Association of Australia. The recommendations are to eat a healthy balanced diet including a variety of foods with breads, cereals and grains eaten in moderation and limiting the intake of saturated fat. A trained Dietitian can help to asses the adequacy of your current dietary intake and provide you with recommendations to improve your overall health and manage your diabetes. A Dietitian can also provide you with the knowledge and understanding of how to read nutrient labels on food so that you are able to make informed decisions about the products you put in to your shopping trolley. Make an appointment to see one of our Dietitians today!  If you have a chronic condition (such as diabetes) you are eligible for bulk billing (no gap). Your GP can write you an Enhanced Primary Care plan, ask them how!