Nutrition - calorie restrictions 2

Tuesday 08 May 2018

Hi everyone, this week’s blog is an extension of last week when I looked at the research that has emerged around calorie restriction and cancer treatment. It is a subject that I have become totally enthralled in because the research appears to be so promising.

When I wrote about calorie restriction I was not very specific about the type of food that should be eaten on the calorie restricted days so I thought I should explain in a little more detail. Again taking my information from research that has been completed on the subject.

What food can be eaten on calorie restricted days?
The regime focusses very much on the hunter gatherer type of diet, also known as the caveman diet. It has been observed that there is very little cancer in groups of people that eat in this way, which seems to make sense from an evolutionary point of view. Since the Neolithic revolution, which meant a transition from foraging to nomadism to agriculture and settlement and a switch from  labour in the field, to a sedentary lifestyle has come more disease. According to professor Aston Director of Public Health, we do not expend 3-4000 calories a day, we eat high density calorie laden food and we are not living the way the human species evolved. He went on to explain that the ‘golden generation’, now in their nineties have really benefited from a traditional lifestyle, walking to school or work, not going everywhere in the car, not having junk food. Basically what the research is telling us is that our genes have not adapted to keep up with the food revolution that has happened in the last 100 or so years.

The hunter gatherer diet differs in 3 main ways from the modern diet.

  1. There was a strong reliance on animal foods making up 45-65% of the diet.
  2. The consumption of Low glycaemic foods mainly from vegetables, berry fruits and nuts.
  3. A complete lack of processed carbohydrate types of foods.

What are the effects of reducing carbohydrates?
The contrast in diets was highlighted in a research paper written in 2011. It appears that by reducing or eliminating the carbohydrates from our diet the level of Insulin and insulin growth factor falls dramatically. This has been shown in vitro (in the lab) to slow the development of tumours. Insulin growth factor becomes raised if we produce a lot of insulin as a result of eating a lot of sugar and carbohydrate types of foods. According to this research paper glucose can have direct and indirect effects on the tumour cell growth.

Unlike normal cells, cancer cells depend on a steady glucose availability in the blood for their energy. In contrast they believe that cancer cells are not able to metabolise significant amounts of energy from fats or ketone bodies. Ketones are a byproduct of protein metabolism when there is no or very little carbohydrate food in the diet. High insulin and insulin growth factor are said to directly promote cell growth.

All of this would indicate that the cancer patients would not only benefit from a calorie restriction but also glucose restriction focussing on increased protein and fat in the diet. When I say fats I do mean the good healthy essential fats that we get from nuts, seeds and oily types of fish not the saturated fats that we get from animal foods like fat on meat and the skin on poultry etc. This type of eating is in line with the Warburg effect.

What is the Warburg effect?
Well as you can imagine they were experiments that were published by a chap called Otto Warburg and his colleagues in 1923. They observed that a tumour converts high amounts of glucose into lactate. Lactate is the fuel if you like. This was in contrast to normal cells which did not take up glucose or produce lactate as a form of fuel in the same way.

When glucose is converted in the body as a form of energy the process is known as glycolysis. Glycolysis literally means the dissolution of glucose. This requires eleven different enzymes so it is quite a complex process. Today the Warburg effect is an established hallmark of cancer amongst many cancer specialists. More recently it has been discovered that cancer cells upgrade the process of glycolysis.

So what’s the bottom line?
All of this is a bit technical I know but very interesting. What all of this is basically telling us is that, according to these particular experts, a diet for cancer should be low or contain very little glucose in the form of sugar or sugary foods or highly processed carbohydrate like cakes, biscuits, confectionery etc.

You may recall a blog that I wrote not so long ago on hidden sugars in the foods and how the food industry has replaced the fat in food to make them low fat with sugar. This is all of course to make food ‘low fat’ and supposedly healthier!!!!

Examples of low carbohydrate diets
A low carbohydrate/ glucose diet is also known as the ketogenic diet, which is void of carbohydrates, other diets are called paleo diet or caveman diet which does include some fruit, nuts and seeds very much like the caveman diet I first mentioned. Dr. Dominic D’Agostini who researches metabolic therapy works at the university in Florida has been very impressed with the results of the Ketogenic type of diet in lab tests on cancer cells. Which is interesting.

Making manageable changes
It is important to remember as with everything that you read, no one diet or eating regime necessarily suits everyone. It is not a case of one size fits all. But I do think that it is worth considering what these experts do say about glucose as we do know that it is not really a food that is conductive to good health whether you have cancer or not.

Blog originally written by Caroline July 2013

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