Having a good understanding the factors involved in weight gain and weight loss can help you adjust your diet to make choices that will move you to your ideal weight. Weight gain often stems from a combination of physical, emotional, and psychological factors, and additionally, with those of us over 50, we simply are losing muscle mass and through inactivity, replacing the muscle with fat. That said, the factor that exerts the greatest effect on weight gain or loss is the stimulation or inhibition of certain hormones.
Hormones are essentially “chemical messengers”. A hormone is a chemical released by a gland that is typically released into the bloodstream to tell certain cells and tissues to take some action that the body needs to have performed.
The release of hormones is controlled by the central nervous system (specifically the brain), as well as by feedback systems that are triggered by certain sensors in the body that monitor the hormone levels in the blood, or monitor the effects of the hormones.
Under normal circumstances, diet, exercise, sleep, stress levels, and exposure to certain chemicals will determine hormone levels and function and the function of certain hormones in turn determines whether the body burns sugar, burns fat, breaks down muscle, or stores sugar, stores fat, or builds muscle.
There are 3 primary hormones that promote fat storage: insulin, cortisol, and estrogen. There are 6 hormones that promote fat burning: thyroid hormone, growth hormone, insulin-like growth factor, glucagon, testosterone, and adrenaline. Even though there are more fat-burning hormones, the fat storing hormones are stronger in their effects.
Fat Storing Hormones
Insulin is the strongest of the fat storing hormones, and works in our bodies to regulate blood sugar levels. Our bodies convert carbohydrates (carbs) into glucose, which is absorbed into our bloodstream. High carb foods produce a lot of glucose, and cause our bodies to release large amounts of insulin. The insulin first stores what glucose it can in the liver and muscles as glycogen, where it can be quickly converted to fuel. The glycogen your body can’t store is converted to and stored as fat.
There are many fat cells in the body and each fat cell can enlarge over 100 times its original size. Fresh vegetables and fruits contain carbohydrates, but don’t stimulate insulin release as strongly as refined sugars and grains because they are high in fiber and nutrients that slow absorption of their carbohydrates into the bloodstream.
Whole grains, because of their fiber content, stimulate less insulin response than refined grains. Whole grains are a much more concentrated source of carbohydrates than most vegetables and fruits (fruits and vegetables have a much higher water content than whole grains) and it is easier to consume more grams of carbohydrate from grain sources than from vegetables and fruits, so even whole grains tend to be problematic for causing fat storage.
Again, insulin is the strongest of the fat storing hormones. A single slice of white bread has enough carbs to cause your body to release sufficient insulin to stop fat burning for 1 to 2 days—regardless of how you eat or exercise. You will only experience sustainable weight loss if you eliminate refined carbs from your diet.[/vc_column_text][vc_column_text]Cortisol is another hormone that stimulates fat storage, primarily around the lower abdomen. Cortisol is released by the adrenal glands and its release is associated with stress. Examples of stress that releases cortisol includes emotional stress, illness or injury, heavy physical exertion, sleep deprivation, etc., all of which cause excess cortisol release and resulting weight gain.
Estrogen is another fat-storing hormone that is produced in ovaries in women and adrenal glands in both men and women. Additionally, estrogen is found in meats, particularly beef and pork, dairy products, and some pesticides and chemical fertilizers. Organic beef and pork, hormone-free dairy, and organically grown produce don’t contain estrogen.
Fat Burning Hormones
ALL of the fat burning hormones are activated / produced by the liver. When the liver is over worked from consuming too much fat, protein, alcohol and medications, it’s unable to process fat burning hormones, so you get fat. Additionally, fluid accumulates, resulting in “beer gut.” Weight gain associated with an overworked liver can be reversed with dietary changes: reduce fat, reduce or abstain from alcohol, limit drugs and medications.
The thyroid hormone is the most powerful and regulates your body’s metabolism. When the thyroid isn’t working properly, the results can include weight gain, fatigue, hair loss, and brittle nails. Thyroid hormone production is stimulated by exercise, and while all exercise is good, primarily anaerobic exercise is especially so.
Adrenaline (also called epinephrine) is a fat burning hormone that increases the rate of blood circulation, breathing, and carbohydrate metabolism, and prepares muscles for exertion. Stress and diet drugs stimulate the production of adrenaline and cortisol, the fat storing hormone we discussed earlier. Adrenaline is fast acting, and produced in limited amounts, whereas cortisol is long acting and is produced over a longer period of time. So short bursts of intense exercise burn fat, excessive exercise or excessive stress will stimulate cortisol release and hinder fat burning.
Growth hormone stimulates the growth of muscle and lean body tissue, indirectly stimulating fat burning, and also stimulates the liver to produce a hormone called insulin-like growth factor (IGF). IGF controls blood sugar levels during long periods between eating – primarily at night when you are asleep. Without adequate sleep (at least 7 hours of RESTFUL) sleep per night, IGF doesn’t function properly. A few hours after eating, your blood sugar begins to fall, and IGF stimulates the burning of stored sugar and fat to keep normal energy supply to the brain. So growth hormone has a second indirect effect on fat burning. Growth hormone (and consequently IGF) is stimulated by anaerobic exercise – which is of relatively short duration but high intensity.
Glucagon is a hormone that can be thought of as the anti-insulin. Like IGF, glucagon stimulates the burning of stored sugar and fat when blood sugar drops too low, but it operates much closer to the time when you eat. It is a counter-balance for insulin. Basically, when you eat and your blood sugar rises, insulin is produced to store the excess, but if insulin takes too much sugar out of the bloodstream, glucagon is released to bring the blood sugar back up again by burning the stored sugar and fat. Glucagon production tends to be stimulated by meals that are relatively low in carbohydrate.
The last major fat-burning hormone is testosterone. Just as men produce some of the “female” hormone, estrogen, women produce some of the “male” hormone, testosterone. Testosterone is produced by the testicles (in men) and the adrenal glands (in men and women). Like growth hormone, testosterone stimulates fat burning indirectly by stimulating muscle growth. Also like growth hormone, testosterone production is stimulated by anaerobic exercise – short duration, high intensity.
To summarize what causes fat storage and fat burning:
Fat storing is largely stimulated by:
- Excess carbohydrate consumption
- Excess stress (physical and/or emotional)
- Excess estrogen and estrogen-like chemicals (such as chemical pesticides, fertilizers, etc.)
Fat burning is stimulated by:
- Good liver function (avoiding the overconsumption of fat, protein, alcohol, and drugs/medications)
- Low carbohydrate consumption
- Anaerobic exercise (relatively short duration, high intensity activity)
- Adequate sleep (at least 7 hours of restful sleep per night)