The cycling of hormones in the body is an incredibly complex and intriguing science. I have read a fair amount from many difference sources on the subject. I recently found a book that offers an interesting perspective on the hormone cycles involved in nutrient metabolism very concisely and very well. It is called The Renegade Diet. If you are interested, a brief summary follows:
The nervous system has two aspects: the sympathetic (which involves outward action sometimes referred to as fight or flight) and the parasympathetic (which involves internal homeostasis or internal maintenance of the body). The sympathetic ‘takes over’ during the day while we are active. The parasympathetic takes over a night when we sleep and the body rebuilds.
Cortisol is a hormone that stimulates action, the sympathetic. It is naturally high in the morning. Insulin is a hormone that drives nutrients from carbohydrates into the cells of the body.
If you eat a lot of carbohydrates, you first get an insulin surge and a lot of energy, but that is followed by a hypoglycemic crash when you become sleepy (think post Thanksgiving dinner).
According to the book, there are three phases in healthy eating which conform to the eating habits that humans evolved through millions of years:
1) The evening feast of protein and healthy starchy carbohydrates like sweet potatoes, squash, pumpkin, white potatoes, etc.
This provides the nutrients for the body to rebuild over night. The carbohydrates spike insulin, which drives nutrients into the cells. Then the hypoglycemic crash occurs enabling one to get to sleep easily so the body can continue to regenerate all night. It is a natural time for Growth Hormone to be high, facilitating growth. This then is also the natural time for the nervous system’s parasympathetic phase. Minimal fats should be eaten at this time since fats and carbohydrates eaten together overwhelm the system and cause nutrients to be stored as fat instead of feeding the muscles and other cells of the body.
2) The 16-hour, overnight fast
This allows the food of the evening meal to be efficiently utilized. Growth hormone remains high throughout the fast, building the body. The fast also gives the digestive system time to rest and restore, rebuilding the enzyme stores, cells, etc.
3) The 8 hour daytime window to eat protein, veggies (for nutrients and fiber), and healthy fats like omega 3s, coconut oil, olive oil, etc.
This keeps the sympathetic nervous system ‘in charge,’ which prevents daytime hypoglycemic crash, thereby providing a full day of energy for an active, bright, clear, and dynamic life. Minimal glucose from carbohydrates in the system during this time has many health benefits:
• If carbohydrates are eaten often, then the cells become resistant to the spike of insulin post carbohydrate ingestion. This in time can lead to obesity and diabetes.
• The fatty acids in the blood are utilized as energy for the day. This ‘teaches’ to body to burn fat instead of storing it.
Too much stress causes too much cortisol to be released which creates abdominal fat and other health disadvantages. Coffee stimulates cortisol so a little in the morning, when cortisol is naturally high, is ok. However, coffee all day long and too much stress over stimulates cortisol, which is a problem.
Then comes the evening meal when the cycle starts again. There are many fine points involved but these are the basics. If you are interested there is plenty to read on the Internet. Many who follow this diet consider themselves to be on the 90% paleo diet.
One last hormone I would like to mention is Leptin. If you diet without a break, leptin forces the body to resist the process and you hit plateaus in your weight loss. Therefore, a couple of times a week, they recommend a fun meal of whatever you want… just not excessive. This actually speeds up weight loss and health.
So, there you have the basics. If you are interested you should certainly learn more about it before trying it out. Needless to say, consulting a doctor for any health issues before trying it out is wise.
Prior to eating along the lines of The Renegade Diet, I followed a more traditional six small meals a day. A takeoff on The Renegade Diet works better for me. The main way I deviate from The Renegade Diet is that I only eat one large carbohydrate meal in the evening, whereas some may eat carbs in the evening over a longer period of time. Also, for vegetarians, getting enough protein can be a challenge, but is certainly doable.
Personally, I find the whole arena of nutrition and physiology fascinating.