The information on this page has been compiled and edited from previously published articles, by Dr. Connie Guttersen.  The articles are not intended as health advice, nor do they necessarily reflect the views and opinions of the California Olive Committee. Always consult your physician on matters of health and wellness.

by Connie Guttersen, RD PhD.

Can an emotion like stress, dictate hunger and even add extra pounds around the waist? The answer is yes. Stress may actually be the biggest eating trigger contributing to those extra pounds. These pounds are a red flag for the increasing risk associated with heart disease, inflammation and type 2 diabetes.

Stress may actually be the biggest eating trigger. A report regarding comfort food as a calming drug, published in the September 2003 issue of Proceedings of National Academy of Sciences by Dallman and co-author Pecoraro suggests that the tendency to overeat during times of chronic stress is biologically driven and is part of a stress response system in the body. Stress alters brain chemicals, inflammatory chemicals and hormones such as cortisol and insulin that increase appetite and cravings for sweets and fats, which in the end promote weight gain. Obesity also causes an inflammatory response leading to an increase of C-reactive protein, a strong marker of inflammation. Neuropeptide Y, another stress hormone that increases with prolonged stress, affects the hypothalamus to increase appetite and decrease metabolism. Neuropeptide Y is stimulated by ghrelin, the hormone known to increase appetite. Ghrelin and leptin are two hormones, which are being studied closely for their counterbalancing effects on appetite.

Leptin is produced by fat cells in the body. It tells the brain to stop eating and provides a sensation of being full or satisfied. Leptin is also responsible for increases in metabolic rate and insulin levels to deliver energy to muscles rather than be stored as fat. It is possible to override this process through long term overeating. Overeating can create a leptin resistance so the body no longer is sensitive to the signals of leptin to stop eating. Most cases of obesity are characterized by high levels of leptin rather than not enough production. This means leptin resistance has occurred. Adequate sleep, weight loss, exercise and stress reduction will help the body be more responsive to leptin again.

Ghrelin is a hormone, which is released when the stomach is empty and growling. It sends a powerful message to the brain that you need food. It does this by stimulating a hormone, which also becomes elevated in response to stress. This helps us understand how stress increases hunger. Dieting through deprivation also increases ghrelin production and sends even more signals to eat. In other words, it is a vicious cycle.

Here is how the cycle works: When prolonged stress occurs, the body releases high amounts of inflammatory chemicals (such as glucocorticoids), insulin and cortisol into the blood. This increases appetite and the craving for sweets and fats leads to extra, unwanted pounds. Most of these pounds will be deposited centrally, or around the waist. The effect of central obesity promotes the further release of insulin, fat into the liver and more inflammatory chemicals. This metabolic cascade more than often then leads to insulin resistance.

Insulin resistance is a group of health risk factors that increase the likelihood of heart disease, diabetes and some cancers. Other risk factors for insulin resistance (besides excessive abdominal body fat) include high blood sugar, high blood triglycerides, high LDLs and high blood pressure. People with insulin resistance don’t always have every one of these risk factors, but usually have many of them. Recent medical literature also suggests that insulin resistance is associated with work-related mental and emotional stress as well as other aspects of a stressful lifestyle.

The link between insulin resistance and obesity is actually a viscous cycle: Obesity contributes to insulin resistance and insulin resistance contributes to weight gain by not processing glucose efficiently. The link between insulin resistance and obesity is another viscous cycle: obesity contributes to insulin resistance and insulin resistance contributes to weight gain by not processing glucose efficiently. Stress can also be viewed as a contributing link to this cycle as it may promote both metabolic conditions.

Insulin resistance is also affected by the type of dietary fat consumed. Preliminary studies in animals and humans suggest that insulin resistance is increased by an increased consumption of saturated fat and improved by the increased consumption of monounsaturated fats and omega three fatty acids.

Emotions are also tied into this cycle of appetite and health. When the level of serotonin in the brain falls, appetite and cravings increase for sweets. Extreme dieting, stress, and insomnia can deplete serotonin levels. There are other brain hormones that also control emotions and appetite. Not having enough of each of the ones listed in the adjoining chart titled “Hormones That Control Emotions and Hunger” put the body in a stress mode, which then results in an increased appetite, which is often referred to “emotional hunger”. Adequate sleep has also been found to be important in maintaining healthy levels of these hormones.

Different foods and their particular nutrients can have an effect on how our brain processes signals related to mood, hunger, sleep and stress. The end result may be less inflammation, reduced production of inflammatory chemicals, cortisol, insulin, and less body fat around the waist.

The B vitamins found in whole grains and vegetables can affect the nervous system. Research also tells us that low carbohydrate diets actually increase depression and anxiety, two situations associated with stress. Emphasizing whole grains is important since they promote the production of the “happy” brain messenger serotonin, which increases a sense of well-being. Thus it is important to eat a moderate amount of the best type of carbohydrates, such as whole grains.

Calcium found in low fat dairy helps counter the effects of lactic acid produced by tense muscles, which is often recognized as an overall achy feeling in the body. Magnesium, found in almonds and whole grains, is important for muscle relaxation. Magnesium has been found to be lower in individuals who have a type A personality or a high stress personality. Fats such as monounsaturated fats in olive oil and nuts and omega three fatty acids in flaxseed and salmon may help counteract depression which may be induced from stress or dieting. These fats also play a beneficial role for  the risk of inflammation. Insulin resistance is also affected by the type of dietary fat consumed. Preliminary studies in animals and humans suggest that insulin resistance is increased by an increased consumption of saturated fat and improved by the increased consumption of monounsaturated fats and omega three fatty acids.

Green, yellow, and orange vegetables are all rich in nutrients and phytochemicals that boost immune response and provide antioxidants, which tend to be depleted during stress. Green tea contains a phytochemical called catechin. Catechin may be linked with a processes, which help breakdown fat and inhibit the formation of an inflammatory chemical, which triggers hunger.

Exercise to Keep Stress Away

Both high intensity and meditative type of exercise provide an incredible benefit against the negative effects of stress. Relaxation is not the only way to beat stress and its negative effects on health. Regular exercise can strengthen the mind, mood, and body. It has been well established that regular exercise is essential for weight loss, improving heart disease and diabetes risk factors, as well as many other metabolic diseases.

Exercise not only improves the body’s circulation and oxygen delivery throughout the body, it alters a wide variety of chemical changes in the brain. The major effect is to boost the activity of mood enhancing neurotransmitters, such as dopamine and serotonin, and even make cells more responsive to leptin to decrease hunger. Exercise also triggers the release of endorphins, which are responsible for relaxation and that “feel good feeling” we get from exercise. Regular exercise that is appropriate and tailored to one’s individual needs is always a sure bet for beating the blues.

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