We face widespread chronic disease, much of it associated with excess stored energy and persistently high insulin levels. This is called insulin resistance, hyperinsulinemia, pre-diabetes, metabolic syndrome or energy toxicity.
The list of conditions discussed in this context is long:
- Alzheimer’s disease
- Asthma
- Osteoarthritis
- Rheumatoid arthritis
- Cancer
- Depression
- Type 2 diabetes
- Fatty liver
- Acid reflux
- Fibromyalgia
- Gout
- Sleep apnea
- High blood pressure
- Osteoporosis
- Stroke
- Coronary artery disease
- Atherosclerosis
- Heart failure
- Erectile dysfunction
- Polycystic ovarian syndrome
- Acne
- Low testosterone
- Enlarged prostate
- Gynecomastia
- Baldness
- Psoriasis
- Lupus
- Peripheral neuropathy
- Glaucoma
- Near-sightedness
- Vertigo
- Tinnitus
- Inflammatory bowel disease
- Sarcopenia
- Tendinitis
- Carpal tunnel syndrome
- Hearing loss
- Macular degeneration
A striking number of adults have at least one condition on this list. Actually, only 12% doesn't have any signs of insulin resistance and is metabolically healthy. These figures are from the United States, so they may not describe every country equally well.
This list comes from a book I just read, The P:E Diet by Ted Naiman, which I recommend to anyone curious about metabolism and ways to reduce risk.
How our metabolism works
Food contains three macronutrients : protein, carbohydrates, and fat. Protein helps build and repair the body, while carbohydrates and fats provide energy. We can store energy in two ways, which work differently:
- Carbohydrates are broken down into glucose and fructose that generate energy. All of the energy that's not used is converted into glycogen and stored in the liver and muscles.
- Fats are broken down into fatty acids that generate energy. All of the energy that's not used is converted into triglycerides and stored in fat cells.
The body can access glycogen more quickly than triglycerides, but glycogen takes more space to store because it is stored with water. That is one reason triglycerides are useful for longer-term energy storage.
The body draws on glucose in the blood and glycogen in the liver, which can store roughly 100 grams. Between meals, the body can increasingly draw on stored fat for fuel.
If you eat carbohydrate-rich foods throughout the day, you may spend less time drawing on stored fat.
Glycogen also provides a quickly accessible reserve for intense effort. You are also able to store about 300 grams of glycogen in your muscles for that, which becomes especially useful during high-intensity activity. For our ancestors, that might have meant escaping a predator; today, it includes high-intensity exercise such as sprinting, climbing stairs and weight lifting. A prolonged bout of high-intensity exercise can substantially deplete muscle glycogen.
The average person may do little high-intensity exercise on a typical day.
When it gets too much
Our bodies are remarkably capable. Why, then, do so many people show signs of poor metabolic health?
One explanation is that we regularly eat energy-dense foods that provide relatively little protein and few minerals, eventually exceeding our capacity to store that energy safely. Fat cells can expand dramatically in size, but they have a limit. As they fill up more and more with fat, they start refusing to store glucose and triglycerides.
Continuing to eat more energy than you use can then cause problems. Insulin will attempt to signal cells to take up more energy but the cells are already full, potentially leaving insulin elevated while energy continues to accumulate.
When your fat cells have reached their maximum size, and you have exceeded your genetic capacity for growing new cells, excess energy is being stored into your visceral fat. Waist circumference can be a useful proxy; one guideline is to keep it below half your height (mine is 0,41 at the moment).
More visceral fat is often associated with greater insulin resistance. Eventually even these visceral fat cells fill up entirely and then your body starts storing fat anywhere it can, including your organs and blood vessels. This is the idea behind a personal fat threshold: the amount of fat your body can store before problems arise.
Exceeding that threshold can contribute to type 2 diabetes, a late outcome of insulin resistance. In the process to get to this point you are probably slowly developing several of the listed ailments above.
Every single person has the ability to grow new fat cells and get fatter prior to developing insulin resistance, to a certain extent. Some people are capable of gaining hundreds of kilos before becoming insulin resistant, others have a low fat threshold. That makes appearances an unreliable guide to metabolic health.
What you can do to avoid problems
Type 2 diabetes is the end stage of insulin resistance, which can follow a long period of excess body fat. Along this entire spectrum, the primary problem is storing too much energy in your body, often driven by eating too much energy.
Four habits may help reduce that risk:
- Eat whole foods, for example (organ) meat, poultry, eggs, fish, vegetables, avocado, berries and cheese. These foods are nutrient and protein dense. These foods can be satisfying, making overeating less likely.
- Fast intermittently, for example eat only in an 8 hour eating window and fast for the other 16 hours, every day. This gives your body a longer break between meals and may help you eat less overall.
- Practice high intensity exercise, for example cycling, sprinting and weight lifting. These activities raise your heart rate and use muscle glycogen. Replenishing that glycogen also takes energy. The extra advantage of weight lifting is that the more muscle you have, the more energy your body is using which may help you manage your energy balance.
- Get enough sleep, that is 7 to 8 hours or more every night, some people may need more. The best way to achieve this is developing a rhythm by going to bed and waking up at the same time all days of the week.