Nutrition – insulin and health

Tuesday 08 May 2018


This month’s blog focuses on the effects of insulin on our health, the Glycaemic Load (GL) of foods and what this means to our health..

So what do I mean by ‘glycaemic load’ or GL?

Well, all foods have been measured and been given a glycaemic number ranging from 100 – 0. The lower the number the food has, the less of an impact it has in the body on insulin release and the better this is for our health. Opposite to this the higher the number, the greater the impact on insulin release. Basically it is a way of measuring if the food is fast at releasing or slow at releasing sugar from the food into the blood.

Generally speaking, foods that have been given a high GL number are fast releasing (40 and above) and known as simple carbohydrates. These are sugar and sugary foods (confectionery, cakes, biscuits, puddings etc), jams, most honey, white foods, processed refined foods, most commercial breakfast cereals, dried fruit, fruit juices, alcohol.

The slow releasing or low GL foods are: all the protein rich foods (eggs, fish, peas, beans and lentils etc), whole grain foods like brown rice, oats and quinoa (known as slow releasing carbohydrates), unsalted nuts and seeds, vegetables, most fruits, good fats like coconut oil, olive oil, rapeseed oil, and cold pressed nut and seed oils.

This is of course at a glance and you can access comprehensive charts from the computer. Two very good books that explain this well and provide useful recipes are by an author called Patrick Holford. One is called, The low GL Diet Cook book and the other Food Glorious Food. Most healthy cook books will focus on using low GL foods.

What are the potential benefits of eating in  a low Glycaemic way?

The benefits of trying to eat in a Low Glycaemic way (low GL) is gathering momentum and popularity among nutritional experts for good reasons, as eating in a low GL way has many health benefits;

  • It focuses very much on natural healthy foods that will have little or no impact on our blood sugar levels and insulin release. Keeping this stable seems to be the key to feeling better and helping to ward off disease.
  • The foods that are low GL help to prevent blood sugar highs and blood sugar lows (hyperglycaemia and hypoglycaemia).
  • Both Hyper and Hypo are extremes that the body has to cope with. When we have extremes this creates internal stress in the body. When we are stressed, for whatever reason, the body will produce another hormone called cortisol which helps the body to adapt to the stressful situation. Short sharp bursts of cortisol are beneficial to us but continued cortisol release will suppress the immune function. So a way to support our immune function is not to allow blood sugar highs or lows by avoiding eating fast releasing carbohydrates and focusing on eating slow releasing carbohydrates.
  • If we do allow our blood sugar to go high, insulin will be released to carry the sugar from our blood into our cells where it is stored as fat. This is the primary role of insulin to keep blood sugar at a healthy level. It is an essential hormone and without it we would suffer from diabetes. Insulin is a very efficient hormone and after the initial sugar high inevitably a few hours later we will experience a sugar low. When we have low blood sugar we will most probably feel tired, crave sugar, lack focus, be headachy, have depression, have mood swings, suffer from poor sleep, and get a bit edgy. Does this sound familiar? I call it the 4 o,clock dip!!!! Unless you are aware of why this is happening the natural thing to do is to eat something sweet. This of course will send the blood sugar high again, more insulin is released, and so we develop the yo yo syndrome of highs and lows. Remember that all this stored sugar is forming fat.
  • As I have said insulin is an important hormone but too much insulin can also disrupt hormone levels. Basically, in our liver we have a protein called the Sex Hormone Binding Globulin, a mouthful I know, but it is the role of this particular protein to support detoxification of excess hormones out of the body via the bowel. Obviously if insulin inhibits this protein from doing its job efficiently this will lead to high body hormone levels. So one way of supporting excess hormone detoxification is to keep insulin levels down i.e. with a low GL diet.
  • As a point of interest I was reading an article this week about research carried out on 4,000 girls and their sugar intake, mainly from soft drinks. The conclusion was that girls with the highest sugar intake started their periods at an earlier age, had the highest levels of oestrogen, and were at a higher risk of developing breast cancer.
  • Insulin has also been shown the cause inflammation in the body by encouraging the release of inflammatory hormones. Inflammation has been shown to drive disease.
  • Lastly but by no means least is the fact that the chemical structure of insulin is very much the same as the chemical structure of a growth hormone. This is called ‘insulin growth-like factor’ (IGF-1). Growth factor encourages cell growth. Before we get too alarmed by this let me explain. From the age that we are born till just beyond puberty we have a very high growth factor level. This is obviously because we are growing and developing into a young adult. When we reach adulthood the amount we produce falls and we produce enough for repair of tissues but not for growth. In a normal cell the growth hormone is bound to another protein which controls its release and use by the body.
  • In a cancer cell the DNA has been damaged which makes them hyper sensitive to growth factors, the growth factor is free or unbound and therefore it has no breaks or protein to control its use and so can encourage cell growth. This fact is one of the primary aims of the ketogenic diet where the basic principles is to keep insulin and glucose levels right down so that they cannot influence the cancer cell.

So where does all of this information leave us? Obviously it would be wise to try and follow a low GL diet but this can be difficult for some people, especially if they have a sweet tooth. Next month I will look at the sugar alternatives that are on the market that will not disrupt blood sugar levels so, hold on, all is not lost.

Make any change manageable
Also one important word, although this low GL method of eating is recommended for many good reasons, I do know that when some people are going through chemotherapy the treatment can do all sorts of things to the taste buds and appetite. I am always keen to point out that during this time it is important to accommodate your appetite and go with the flow, knowing that as soon as the taste buds and appetite return to normal you can go back to the low GL way of eating. I know that some people beat themselves up over this. We have to remember that we are not super human and so just do your best according to your circumstances.

Blog originally written by Caroline, Nutritional Therapist - links updated April 2020

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