By Tracey Greenwood, Ph.D.
Excess abdominal fat isn’t just unattractive; it also increases your risk for many different diseases. Here are seven tips to help you bust that guy and shed those unwanted pounds.
FOLLOW A LOW-CARB DIET
In the body, dietary carbohydrates, sugars, and starch are converted to glucose, which indirectly instructs the pancreas to release insulin into the blood. Insulin not only transports glucose into the cells, it stores glucose as glycogen in the liver and muscles. Insulin is the primary fat-building enzyme, converting glucose to fat. When the liver and muscles are filled with glycogen, insulin turns excess glucose into body fat. Insulin also inhibits lipolysis, and decreases the body’s ability to break down stored fat. Diets that are high in carbohydrates are a contributing factor toward weight gain.
One of the major health benefits of a low-carbohydrate diet is weight loss. A low-carbohydrate diet will lower the amount of stored glycogen in the muscles and liver. This will cause fuel sources to shift from glucose to fatty acids, thereby increasing the rate of lipolysis and beta oxidation to make ATP for energy during exercise. Lowering your intake of carbohydrates is one way to lose excess abdominal weight without having to consciously restrict calories. A low-carbohydrate diet lowers blood glucose in diabetics and it improves insulin sensitivity, which is a precursor for The Metabolic Syndrome. A low-carbohydrate, non-restricted calorie diet is generally defined as less than 10 percent of total caloric intake or no more than 20 grams of carbohydrates daily. Most low-carbohydrate diets replace carbohydrates with healthy sources of fats and proteins.
When choosing which carbohydrates to include in your diet, you should refer to the glycemic index scale. Carbohydrates are given a measure known as their glycemic index (GI), which rates their effects of blood sugar levels. Carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream have a high GI; carbohydrates that break down more slowly, releasing glucose more gradually into the bloodstream have a low GI.
Low glycemic index carbohydrates only cause a gradual rise in glucose and limit the spikes in insulin in the body. Low glycemic carbohydrates also help you to feel fuller, and give you more energy. Low glycemic index carbohydrates will have a GI rating of 55 or less and will consist of fruits and vegetables, legumes, whole grains, nuts, fructose, and products low in carbohydrates. Medium glycemic index carbohydrates will have a GI rating of 56-69 and consist of whole-wheat products, brown rice, sweet potatoes, and sucrose products. High glycemic carbohydrates have a rating of 70 and above and typically consist of baked potatoes, watermelon, white bread, white rice, breakfast cereals, and glucose.
TRY THE MEDITERRANEAN DIET
If sticking to a low-carbohydrate diet isn’t for you or if you’re looking for a heart-healthy eating plan, then the Mediterranean diet might be more appealing. The Mediterranean diet incorporates the basics of healthy eating, which includes olive oil and perhaps a glass of red wine. Research has shown that the traditional Mediterranean diet exerts a cardio-protective effect, reducing the risk of heart disease. Increasing scientific evidence suggests that the Mediterranean diet may not only reduce the risk of cardiovascular disease, but also reduce the risk of cancer, cancer mortality, Parkinson’s and Alzheimer’s diseases, as well as preventing obesity.
The staples of the Mediterranean diet include fresh fruits and vegetables, whole grains, nuts and seeds, legumes, seafood, yogurt, small amounts of wine and olive oil. Olive oil contains oleocanthal, which may reduce inflammation and prevent conditions like heart disease, diabetes, arthritis, Alzheimer’s, and autoimmune diseases, as well as certain cancers. This diet focuses on portion control, emphasizing small portions of high-quality food.
Healthy fats like olive oil and nuts keep you feeling fuller longer than diets that restrict fat or forbid fat altogether. Instead of limiting total fat intake, the Mediterranean diet makes health-wise choices about what kinds of fats you should consume. It focuses on monounsaturated fat found in olive oil, nuts, and avocados; polyunsaturated Omega-3 fatty acids, found in fatty types of fish such as salmon, tuna, sardines, and trout; and fats from plant sources, like flaxseed. This diet also limits your intake of processed and packaged foods, keeping your intake of unhealthy trans-fats extremely low.
A study performed by the University of Navarra in Spain, consisting of more than 10,000 men and women adhering to the Mediterranean Diet, demonstrated a decrease in weight gain and obesity. Another European study, which included close to 500,000 men and women from 10 different European countries also following the Mediterranean Diet, found a decrease in waist circumference and abdominal obesity. The Mediterranean Diet not only proves to decrease your risk of cardiovascular health but it also prevents abdominal obesity.
EAT MORE FIBER
Eating more fiber could also have a big impact on decreasing abdominal fat. A study performed by The National Institute for Public Health in Bilthoven, Netherlands, showed that people who consumed 10 grams or higher of fiber per day decreased their total bodyweight and abdominal fat. A significant source of dietary fiber is defined as a food that contains a substantial amount of dietary fiber in relation to its calorie content and that contributes at least 2 grams of dietary fiber in a selected serving size.
Fiber helps keep our waistlines slim by producing regular bowel movements and lessening the belly bulge. Fiber also wards off certain diseases. Carcinogens in the intestines bind to it and move through our colons more quickly than they otherwise would, reducing the risk for colon cancer. Fiber’s greatest value, however, is in helping to keep us slim. The recommended daily intake of fiber for adults is 20 to 30 grams per day, with an upper limit of 35 grams. Good sources of fiber include whole grains, vegetables, fruits (preferably with the skin), nuts, seeds and legumes.
CUT BACK ON SUGAR
Most junk foods and processed foods consist of refined carbohydrates and sugars, which when eaten quickly raise blood sugar levels, leading to an increase in appetite and a reduction in the body’s ability to burn fat. Processed foods are highly favored by the food industry and the consumer because they are very inexpensive to produce and are specifically designed to taste good. The enormous abundance and availability of these foods is evidence that they are a staple of the American diet, and this is a major contributor to the prevalence of obesity.
Foods that are high in sugar or refined carbohydrates are digested into large amounts of glucose that quickly enter the bloodstream and cause a rapid rise in blood sugar, resulting in an augmented release of insulin. The additional insulin can impair the body’s ability to maintain consistent blood sugar levels, which can lead to insulin resistance and type 2 diabetes.
When sugar is consumed, it can be converted to glycogen and stored in muscle or the liver for future use. Many people consume an alarmingly high amount of carbohydrates that significantly exceed their storage capacity for glycogen. When this happens, the sugar resulting from carbohydrate digestion is converted to body fat. Many of the people who consistently consume the processed foods that contain sugar and refined carbohydrates are significantly overweight. In addition, these foods have been shown to encourage overeating, which further increases potential for weight gain.
STOP LATE-NIGHT EATING
To successfully lose weight, the last meal you eat should be at least two hours before you go to bed. The problem with late night snacking is that there isn’t much physical activity done afterward, and this will cause high blood sugar levels and no energy expenditure, causing the excess sugar to quickly be converted to body fat.
Your body begins to shut down a few hours after dinner preparing for sleep, causing your metabolism to become minimized at night. This natural slowing down of your metabolic rate overrides any metabolic or thermogenic boost you would obtain from eating. During sleep, the minimal amount of calories you will burn are those used for cardiovascular and respiratory function and REM sleep. The last meal you eat for the day should consist mainly of lean protein and low glycemic carbohydrates such as fruits and vegetables. You should avoid all starchy carbohydrates like bread, pasta, rice, potatoes, etc.
GET SOME SLEEP
Short sleep duration is associated with obesity, increased abdominal fat, and type 2 diabetes. Sleep patterns consisting of less than 5 hours per night are associated with insulin insensitivity, leading to impaired carbohydrate oxidation and increased risk of type 2 diabetes. The growth hormone (GH) is secreted during the first round of deep sleep. Shorter durations of sleep cause lower GH secretion resulting in the fat-gaining process. Stress imposed on the body due to lack of sleep causes enhanced levels of cortisol in the blood. Cortisol interferes with falling asleep or remaining asleep. The cycle of hormone output, insulin release, and hunger continues. Shift work with its interrupted sleep patterns can be directly linked to belly fat deposit.
Cortisol causes fats and sugars to enter the blood circulation to increase energy for handling stressful situations. Shorter sleep patterns cause an increase in appetite the next day and most often fatty foods are eaten. The blood glucose increases and then decreases, resulting in the repeated presence of cortisol, resulting in a vicious cycle and increased abdominal fat.
EXERCISE CONSISTENTLY
Although diet plays the most important role in losing abdominal fat, exercise is a key ingredient in the belly fat-burning process. During exercise, the stress hormones norepinephrine and epinephrine are released, which stimulate lipolysis, the breakdown of stored fat molecules. When these hormones are released into the blood, they cause a metabolic reaction, resulting in the activation of the enzyme Hormone Sensitive Lipase (HSL). HSL triggers the breakdown of a stored triglyceride molecule in adipose tissue to release free fatty acids, which can then be further oxidized, producing a loss of body fat.
Combining different types of exercise is the best cocktail to burning fat. The American College of Sports Medicine (ACSM) and the American Heart Association (AHA) recommends moderately intense cardio-respiratory exercise 30 minutes a day, five days a week, or vigorously intense cardio-respiratory exercise 20 minutes a day, three days a week, with the addition of eight to 10 strength-training exercises (8 to 12 reps of each exercise), at least twice a week.
During aerobic exercise, your body goes through several stages before it reaches the point where you are burning fat. You will hear people say that you are only burning sugar (carbohydrates), not fat, during the first 10 minutes of exercise. This is true to a certain extent. Stored carbohydrates in the form of glycogen can be used for fuel during exercise up to 60 minutes, depending on the intensity of the exercise and the type of diet consumed. If you consume a low-carbohydrate diet, glycogen stores will be depleted sooner, causing lipolysis to be activated sooner rather than later. Also the intensity of the exercise will determine if you are utilizing your stored fat.
A study performed by The Cooper Institute in Dallas found that the duration of aerobic exercise was more beneficial than the intensity of exercise for decreased bodyweight and waist circumference. A longer duration produced the greatest loss of bodyweight and body fat.
Weight training is a vital component in decreasing abdominal fat and the key to burning fat at rest. Weight training is an anaerobic activity that will often cause you to burn more calories per minute than aerobic exercise. The calories that you are burning during weight training exercises are mostly calories from carbohydrates (because weight training is usually shorter in duration than endurance exercise), but the calories you burn at rest are mostly calories from fat. The reason you are burning fat at rest is because weight training increases lean muscle mass, which is highly metabolic and therefore increases your basal metabolic rate, which uses your stored fat as energy. To make your body the ultimate fat-burning machine, you should do a combination of aerobic (cardio) and anaerobic (weight training) exercises.
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