OBESITY & DIETARY FIBER

Written by Slawomir (“Swavak”) Gromadzki, MPH

Apart from regular physical activity there are some excellent nutritional principles which will help you to burn more and absorb less calories. One of the best nutritional solutions to the high calorie consumption as well as the overweight and obesity problem can be found in the promotion of well-balanced plant-based diet but on condition that it consists of unrefined products. Vegan diet which is rich in whole and unrefined foods, like whole grains, fruits and vegetables, legumes (beans, lentils, chickpeas, etc.), nuts, and seeds, contain high concentrations of fibers, antioxidants, and numerous other phytochemicals which proved to have protective abilities against obesity and other chronic diseases.

In one of the recent studies published in The Journal of Nutrition, a group British researchers demonstrated that women whose breakfast had low-glycemic index (whole grain products, non-instant oatmeal, fruits, and other high in fiber plant foods) were able to burn 50 % more fat during 1 hour walk 3 hours after the breakfast than women whose breakfasts were high in glycemic index (white flour products, ice creams, granolas, white bread, cornflakes with milk, jam, carbonated drink, etc.). Both breakfasts contained equal amounts of carbohydrates, protein, and fat, but the low-glycemic index breakfast contained 2 more grams of fiber, compared with the high-GI breakfast. Apart from greatly increased efficiency in burning fat, consuming low-glycemic and higher in fiber foods for breakfast also reduced the appetite and tendency to overeat during the next meal! British researchers concluded that unrefined plant foods rich in complex carbohydrates and fiber which at the same time have low glycemic index may encourage our body to burn fat rather than using only blood sugar as a source of energy. This very important study again proves that it is not the amount of calories which is most important in dealing with obesity and overweight but the quality of food is the key to success. It means that our meals should be rich in fiber and at the same time low in GI!

Plant-based diet rich in unrefined carbohydrates is known to be the best source of long-term energy or sustainable energy because it takes much longer time for them to be absorbed by your body than refined carbohydrates. For this reason you need to avoid refined foods such as all animal products (meat and dairy), fats, margarines and oils which are deprived of fiber and very rich in calories, or refined carbohydrates such as sugar, white flour products, white rice, etc.

According to nutritionist Professor Brittany Vester Boler “Fiber makes animals feel less hungry or increase feelings of satiety through several mechanisms”. The more fiber in your diet the less calories you will absorb. In addition to that, a lot of fiber in your diet will prevent you not only from developing obesity, but also from many other health problems such as cancer (especially colon cancer), heart disease, or diabetes. A high-fiber diet is very healthy because fiber absorbs bad cholesterol (which is a form of fat too) and toxins, and causes stool to pass through the colon easily and quickly. The best proof that your diet is high in fiber (vegetables, fruits, whole grains, legumes, seeds, and nuts) would be a large, soft, and bulky stool.

What you really need is to start consuming large quantities of foods which are not only tasty but also high in minerals, vitamins, fiber, and phytochemicals. By doing this you will keep on losing weight without counting calories or feeling hungry. It means that even if you consume more calories than your body needs (on condition that they are mixed with the right and unrefined foods which are high in fiber and nutrients), you will still be able to reduce your body weight to normal and shouldn’t lose this positive effect as long as you stay on this tasty and not difficult to follow diet. So, please, throwaway ideas about counting calories because as long you eat the right type of food you can eat as much as you want and still lose weight.

In a 1991 study conducted by Prof. Shintani and his colleges, overweight participants were allowed to consume as much as they wanted of unrefined (high in fiber) low-fat, plant-based foods. In just three weeks they lost an average of 7.8 kg. The chapter revealing the results of the study states that, “some participants indicated that at times (due to high satiety level) they could not finish their snacks. Weight loss was dramatic during the program, with an average weight loss of 7.8 kg in just 3 weeks. Total serum cholesterol concentrations decreased an average of 14.0%. Serum triglyceride levels as well as systolic and diastolic blood pressures fell significantly. There was a striking decrease in average serum glucose.”

In one of the popular magazines it was reported that Oprah Winfrey and 300 members of her staff decided to go vegan for one week. That meant no animal products, no meat, no fish, no milk products, no eggs, and no foods with any animal ingredient. As a result, after only one week, the participants of that vegan challenge lost together a total of 500 pounds. And, according to Oprah, they used a record amount of toilet paper.

The refined plant foods such as refined carbohydrates are regarded as the leading cause of obesity, diabetes, and cardiovascular problems. It is so because refined carbohydrates (such as white flour products) are deprived of nutrients and eventually they are converted in your body to sugar. Examples of foods which contain refined carbohydrates include white flour products (white breads, pastries, cakes, pasta, pies, biscuits, etc.), white rice, cereals, sweets, candy, alcohol, and many others.

Always choose products that are high in dietary fiber. It is extremely important in case of overweight because according to scientific data the diet high in fiber (whole grain products, raw vegetables, fresh and dried fruits, nuts, seeds, legumes, whole meal flower products, brown rice, etc.) is more efficient in reducing overweight and obesity than low fat diet!

Remember, however, that there is no fiber in animal foods. Fiber is found only in unrefined plant foods, thus the less animal products (meat and dairy) are consumed, and the more plant-based products rich in fiber in the diet, the better should be the results. So the best thing you can do to reduce your body weight and get rid of any health problem is to say mooo to meat and dairy!

The benefits of such rich in fiber diet are manifold. It not only reduces the absorption of fat, but also lowers blood glucose and cholesterol levels, reduces the risk of certain types of cancer, and increases satiety, as high fiber food is digested more slowly.

Legumes such as beans can act as a weight-loss and anti-diabetes food because they are digested very slowly, thus having a stabilizing effect on blood sugar level, which helps to prevent food cravings and promotes satiety. When you compare, for example, cooked beans or other legumes with the same amount of lean meat you will see that there is not much difference between them as far as calorie content is concerned. Meat would have only about 30% more calories. But, it is fiber that makes difference, because unlike meat, beans contain a lot of fiber which causes that only half of the calories from them would be absorbed! Besides, unlike meat beans have been shown to lower cholesterol levels and reduce heart-disease risk. The fact that beans, lentils or chick peas are high in dietary fiber, means that they will fill you up faster. That is why beans and other legumes can boost your weight loss efforts. In addition, since legumes contain resistant starch which digests very slowly, your blood sugar level never gets high and therefore, insulin is not released and you won’t get hungry again quickly. That is another reason why you need to avoid refined carbohydrates such as white bread, white pasta, noodles, spaghetti, cakes, doughnuts, pancakes or other foods containing white flower and sugar. For the same reason avoid white rice and other refined foods too.

If possible buy a bread maker and make your own bread. If you buy bread make sure it is made with whole-grain flour, which has almost 15 g of fiber per cup, while white flour has only 3 g per cup. Similarly, switching from refined cereal to bran or oat flakes at breakfast will dramatically increase your dietary fiber intake. The best and most healthy types of bread are the following: whole-grain rye crackers, also called crispbreads such as Ryvita Crispbreads, Biona Organic Rye Bread (no yeast), or German Rye Bread which consists of the following ingredients: Whole Kernel Rye, Water, Whole Meal Rye, Salt, Oat Fibre, yeast. All the above mentioned breads are healthy, nutritious and packed with fiber.

Also legumes, nuts and seeds are very rich in fiber (over 10 g of fiber per cup). Meat and dairy products including eggs, milk products, cheeses, chicken, beef, fish, and all other animal foods contain no dietary fiber. The same is true for any refined sugars and oils.

In case of obesity and overweight it is usually recommended to avoid sweet fruits such as bananas, grapes, mangos, and dried fruits (raisins, dates, apricots, figs, etc.) because of their high sugar content. However, we need to remember that although it is true they are high in sugar, yet these fruits are also high in fiber which causes that carbohydrates are digested and converted into simple form of sugar very slowly. For this reason there is no need for pancreas to release too much insulin in order to lower the blood sugar level. Too much insulin (which increases appetite) is produced only when you consume refined carbohydrates (anything which contains white refined sugar and white flour).

Apart from that, sweet unrefined carbohydrates such as fruits (especially bananas and dried fruits) are the best type of food to increase production of serotonin without which it is very difficult to control appetite and negative emotions. Some studies also suggest that without sweet unrefined carbohydrates (fresh and dried fruits) in our diet it is impossible for amino acid tryptophan, from which serotonin is produced, to pass the blood-brain barrier. For this reason, in case of obesity and overweight, I wouldn’t suggest to avoid sweet and dried fruits. You still need them but rather moderate amounts. Remember that the most important food for you is fresh cold-pressed vegetable juices and raw vegetables.

The same could be said about nuts and seeds. Yes, they are relatively high in fat but they also are high in fiber. And in addition, they are the best source of vitamins B, zinc, magnesium, or ALA omega 3 fatty acid which helps to fight obesity and gives many other benefits. Numerous studies have demonstrated that including nuts and seeds in the diet can help aid in weight maintenance and diabetes prevention. So, like sweet fresh and dried fruits, you should also include unroasted seeds and nuts in your healthy diet but you probably don’t need more than a handful of them a day.

Try to consume at least 20 up to 50 g of fiber each day. Always choose foods in which calories are accompanied with fiber and adequate amount of vitamins and minerals. Increase consumption of unrefined plant-based foods especially cold-pressed vegetable juices, raw vegetables, whole grain products, or fruits, and eliminate or at least reduce the intake of animal-based foods, sweetened beverages and foods which are high in empty calories, refined sugar, white flour, and fat. Remember that being on a steady unrefined plant-based diet is much more effective than so called Yo-Yo therapy (repeated losing weight and gaining it again).

 

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