I am a Physician specializing in Endocrinology, the study of the metabolism and also the hormones. We can measure the levels of many hormones in the body necessary for smooth functioning of the metabolism and tend to supplement when the hormones are low or absent ( Hypothyroidism when you are given Thyroxine or when a hormone is absent, as in Type 1 Diabetes), there are conditions when they are too much as well.
When you visit these United States of America, you would be impressed with very many things, including the amount of vitamins, supplements and other things (Turmeric is the darling now) they swallow. Why are they insisting on gluten free stuff if they do not have gluten intolerance? No one says I will drink Lactose free milk but it is good to drink it if you have lactose intolerance which is quite common.
Americans are very good at selling things and promoting things. USA is full of exercise gurus, nutrition gurus, finance gurus and most of them are not qualified but they know how to MARKET it and EXPORT it.
While they put so much emphasis on physical exercise and jogging and running and cardiac exercises and all sorts of gym based exercises, they eat food which is nutritionally garbage and as you can see with their obesity rate. Dont get me wrong, good food is available in the USA and many people eat well but a large proportion eat bad food for various reasons, much of it socio cultural and economic in nature.
A colleague of mine often asks me metabolism related questions and I am glad to oblige and I had requested that she put on a Continuous Glucose Monitor which would give the sugar reading at any time of the day or night
She exercises a lot (excessively in my opinion) and I was surprised when she showed me her CGM reading.
Before she left home for work, the Blood Sugar was 108 mg/dl very much the normal for her. then I wondered what made the sugar go up nearly a 100 points during the drive from home to work ..You could ask her questions like (most doctors would ask): did you eat something, did you drink some fizzy sugar drink ? But if you an anthropologist, you would say: can you explain why your sugar leapt a 100 mg/dl
The answer was forthcoming. She eats vitamin and food supplements in the form of gummies on her way to work, about 8 of them in total.