Why what we eat is the key!
So here is the follow up of to my last blog in which I questioned the need for exercise in order to lose weight. As it turns out exercise is a very small part of the equation, and more importantly to the chemistry (some would say biology) of weight gain and loss.
Exercise is an essential part of our lifestyles, it is good for the gut, good for the body and definitely good for the brain but not so much essential to lose weight. Also I believe that we need to steer away from the “calories in= calories out” theory.
It is so simple that I understand why people buy into it, but then you actually look into it both theoretically and practically it does not work. We have to be a little bit better informed and understand that it is the substance of those calories and what they are made up of that really counts.
1000 calories of carbohydrate or 1000 calories of fat or 1000 calories of protein will be digested and broken down into very different things and used by the body in different ways. So lets look at what happens to each of these food types
Lets not be afraid of healthy fats, if we called it something else we might be less terrified. Olive oils, nut oils, most vegetable oils, animal fats- all that have not been processed and changed into something artificial are good. They are broken down in our Small Intestine by bile into much smaller particles where the enzyme Lipase can break it down into Fatty Acids and Triglycerides. Fatty Acids and Triglycerides can be used for rebuilding and for energy conversion. Triglycerides are a type of fat found in specialised fat cells called Adipocytes. Your body will turn unused calories from fat into Triglycerides that it does not use straight away. They are stored inside your fat calls as energy to be used later. Fatty Acids play a massive part in developing and repairing your body and managing inflammation in the body. Saturated fats contribute to increasing inflammation in the body, where as fatty acids such as Omega 6 and Omega 3 decrease inflammation in the body, both are important in development.
Protein is broken down by the enzyme Pepsin in the stomach and passes into the Small Intestine and broken down further into Amino Acids. These Amino Acids are then used for tissue repair and building muscle, but offer very little energy.
Once Carbohydrates are digested they break down into sugar. Different Carbs break down at different rates, know as Glycemic Index, but eventually it all becomes sugar.
Once sugar enters your digestive system you release insulin which is the hormone that decides what your body is going to do with the sugar. As discussed in my last blog we store sugar as glycogen in our muscles, our liver and a bit in our blood and this is immediately available to fuel day to day body functions and also to cover the increased energy needed for activity or exercise.
So we have a store for glycogen, probably the equivalent of 1500kcal to 2500kcal depending on age, sex, body type, activity level. When we introduce more sugar from food we replenish the store and then insulin decides what to do with the rest. We either use it up or store it as fat for later use. We are not really designed to have food available at all times, we were designed to be able to deal with a bit of feast or famine. Only in very recent history have we had all food available at all times. Currently, expert advice, suggests that up to 300g per day of carbohydrates is desirable. My research would suggest that only 100g of carbohydrate per day is required to maintain normal body functions, repair, brain activity and a moderate level of exercise.
100g of carbohydrate is not huge but if we want to lose weight it is possibly a decent measure.
Now heres the magic! What happens if we can reduce our carbohydrate intake and deliberately run down our glycogen stores? Unlike reducing our calorie intake across the board which simply reduces the bodies capacity to function by the equivalent amount, if we reduce our glycogen stores we are able to replenish from within and start to use our fat stores as energy.
The hierarchy of energy goes like this- first we use the stored glycogen. Once this store is depleted we begin Gluconeogenesis (gluco=glucose, neo=new, genesis=to make) it takes place in the liver and converts fat back to glucose. We are able to maintain the required energy levels by using fat stores so we don’t need the intake of carbohydrate to sustain this.
Deliberately reducing our glycogen stores is know as ‘Ketosis’ and will start the process of gluconeogenesis after 24 hours of restricted carbohydrate intake.
Getting to a ‘Ketogenic’ state typically requires reducing carbohydrate intake to less than 100g per day and increasing protein and fat intake. It often is associated with rapid early weight loss, as glycogen is 75% stored with water, so burning 1g of stored glycogen, also uses 3-4g of water. But once you are through the early stages there will see a steady reduction in weight and more importantly a reduction in body fat as it is used up to maintain energy demands.
The beauty of the whole system is that we are stimulating how are bodies were designed to maintain energy levels. More importantly it is sustainable, not just a quick 6 week crash before summer comes but a sensible look at our daily food intake to 100g or less. Nothing weird, no juicing, no shakes, no starvation or guilty feelings or fighting with your inner chimp about what to eat.
So, there is my thought for the month. Yes we do need exercise, but to lose weight we need to focus on the make up of our food and learn new habits that we can live with forever.
Current expert advice is dubious, a recent panel on Radio 4s ‘The Food Programme’ discussed some of the history of expert advice in the food industry, and they all accepted it was based on some very thin scientific evidence.
A plan of 100g of carbohydrates, increased healthy fats and protein and weight loss is possible and functional.