Being overweight is the result of an unbalanced diet
The prevalence* of being overweight and obese in recent decades is the result of an unbalanced diet, which means consuming calorie-rich but nutritionally poor meals which result in many chronic diseases (high blood pressure, type 2 diabetes, cardiovascular disease, but also susceptibility to infections).
Studies indicate that overweight 18-year-olds are 2 to 3 times more likely to get diabetes in ages 30 to 50 than people with a stable body weight. With every 5 kilo increase in body mass, the systolic pressure rises by 4,5 mmHg on average.
Reducing body weight in obese people by 5% significantly reduces risk factors for many chronic diseases.
Any diet with a limited energy intake will result in weight loss, but the key question is how to maintain such a condition in the long run. On average, 20% of overweight people successfully achieve long-term weight loss (at least one year) if the reduction is defined as a loss of at least 10% of the initial body weight. Return to initial body weight during a single year is associated with an improper or unbalanced diet, increased energy intake, excessive consumption of energy-rich foods and reduced physical activity.
The health benefits of fiber
In addition to the global increase in the prevalence of obesity, the focus of research is finding solutions or developing products with reduced caloric and increased nutritional value to help prevent and treat the metabolic syndrome**, which also includes being overweight.
Promoting the modification of eating habits is considered a logical and practical initial method in controlling energy intake and body weight.
Epidemiological studies have shown that higher fiber intake correlates with a lower body weight, body mass index (BMI), waist circumference, and improved lipid profiles.
Although the health benefits of fiber are well known, people generally do not ingest the required amounts in their daily diet.
Dietary fiber is the part of a plant that gives it shape and structure and this is their simplest definition. They pass through the digestive system intact because our body cannot digest or absorb them. A diet rich in plant foods can provide the recommended daily fiber needs (25 g for women and 30 g for men), but today’s lifestyle and a diet rich in meat, dairy products and refined carbohydrates (which are low in dietary fiber) provides only up to 15 g of fiber per day. Dietary fiber is divided into soluble and insoluble fiber.
The transparent scales of the seeds of the desert Indianwheat (Plantago Ovata) are called psyllium. It is a mixture of polysaccharides containing galacturonic acid with a soluble and insoluble fiber ratio of 70:30.
By grinding and sifting, flakes are turned into a powder that can be enriched with food (bread, breakfast cereals, pasta), and it is also popular as a dietary supplement due to its wide range of proven health benefits.
Psyllium showed lower fermentability compared to other types of soluble fiber, which is associated with a lower feeling of bloating compared to traditional fibers represented in the diet.
Psyllium scales swell in contact with water and create a form of a gel, and by stimulating muscle contractions that allow easy movement of food through the digestive tract (peristalsis) and increasing the volume of stool, they promote bowel emptying. At the same time, these fibers absorb toxins and pathogenic intestinal bacteria and control the absorption of glucose into the bloodstream, and consequently the accumulation of fat.
Data from available peer-review articles, as well as a number of individual studies, record the beneficial effects of psyllium on glucose and insulin homeostasis, lipids, body weight, body composition and appetite, and gastrointestinal tract plays a role through intestinal motility modulation, absorption, intestinal microflora, and fermentation.
Psyllium has a low caloric value – 100 g of the product has 187 kcal, and the daily recommended amount of psyllium provides only about 30 kcal.
Psyllium fiber has been shown to be effective in people on a reduction diet with the goal of regulating body weight.
Numerous studies to date have shown that consumption of psyllium, a non-fermentable viscous soluble fiber that forms a gel, in amounts of 6-15 g per day can reduce the risk of metabolic conditions by improving glucose levels and insulin response, as well as lipid profiles and body weight.
The results of one study show that the intake of an additional 14 g a day of dietary fiber for more than 2 days can lead to a reduction in daily energy intake of 10%. A separate study showed a lower total daily fat intake in people who consumed psyllium with water three hours before a meal, and subjects felt more satiated one hour after a meal compared to the control group.
The positive effects of psyllium also resulted in obese people who took 3 g of psyllium three times a day with a reduction in energy intake. Over a period of 16 weeks, an average weight loss of 4.5 kg was recorded, and there was a drop in LDL cholesterol levels.
Abdominal obesity or increased waist circumference increases the risk of cardiovascular disease. Significant weight loss and reduction in waist circumference, as well as improvement in body composition (reduced fat percentage), occurred after individuals ingested 15 g of psyllium daily for one year with a normal diet (divided into three meals). After only three months of the study, a reduced proportion of fat in the total daily energy intake was recorded in people who consumed psyllium in contrast to placebo (5g / day of rice flour) where the proportion of fat in the daily diet was still too high. Consumption of psyllium fiber has resulted in positive changes in eating habits as well as maintaining these changes. According to the author, such a result is due to a prolonged feeling of satiety in the post-meal phase and consequently reduced food intake during the day. Most importantly, the individuals maintained the achieved optimal body weight in the long run with the recommended eating habits.
The logical conclusion of all the above is that the consumption of soluble viscous psyllium fiber can be a useful tool for the reduction and long-term maintenance of ideal body weight.
Psyllium fiber regulates appetite
The effect of psyllium on body weight is probably due to its effect on appetite regulation, which has been confirmed by numerous studies. The feeling of hunger, or appetite, encourages us to eat when we are hungry, which supplies the body with vital nutrients. Regulation of hunger and satiety is a complex process, and certain hormones (insulin, gastrin, leptin, ghrelin, PYY, and cholecystokinin) play a significant role in this process. The amount and composition of food affects the synthesis and secretion of digestive hormones.
Controlling hunger between meals is a challenge for many individuals because appetite is affected by a multitude of biological, behavioral, and environmental stimuli, and popular reduction diets and strict and complex diets, frequently carried out without professional supervision, can often impair health.
The findings are conducive to foods rich in fiber that have a positive effect on satiety and delay the desire and need for food intake.
The effect of psyllium on the feeling of satiety was investigated in a clinical trial in which subjects consumed 3.4 g, 6.8 g and 10.2 g of psyllium before breakfast and lunch. The results showed the effect of psyllium on reducing the feeling of hunger and desire to take food between meals and an increased feeling of fullness of the stomach compared to people who did not take psyllium. The amount of 10.2 g of psyllium with a standard meal resulted in a feeling of fullness and satiety six hours after a meal compared to a placebo. The same result was obtained by consuming 7.4 g of psyllium fiber during the day.
According to previous knowledge, it is recommended to take psyllium fiber at least twenty minutes before a meal in order to develop a feeling of a full stomach and reduce the total food intake.
The properties of soluble dietary fiber on the feeling of satiety are explained by various mechanisms, and relate to several stages in the process of appetite regulation, such as taste, gastric emptying, absorption and fermentation.
The hydrophilic properties of psyllium (each gram of psyllium retains about 10 g of water) lead to the formation of a viscous gel. Increased meal viscosity as a result of soluble fiber intake can have several effects: delaying gastric emptying and slowing intestinal nutrient transit, reducing the interaction between nutrients and digestive enzymes, delaying nutrient absorption, and consequently prolonging the feeling of satiety. The influence on the feeling of satiety is the result of several factors, physical properties of the fibers (gel formation and changes in the viscosity of gastric contents), modulation of gastric motor function and postprandial release of glucose and insulin.
Fiber can also affect the taste of food and possibly reduce the amount of food taken. Soluble psyllium fiber stimulates the growth of beneficial bacteria that contribute to the development of the intestinal microflora, which, also according to research, affects the regulation of body weight.
It can be concluded that the addition of psyllium to the diet in acceptable and well-tolerated doses can significantly affect the feeling of satiety between meals and the regulation of appetite, and thus the control of body weight.
How to consume psyllium fiber?
Psyllium should be taken together with liquid, preferably water, but can also be taken with fruit and vegetable juices, soups, yogurt or milk. When starting to take psyllium, the appearance of mild cramps is possible in some cases, most often caused by insufficient fluid intake.
Due to the action mechanism, taking high doses (more than 30 grams per day) can disrupt the absorption of drugs, reduce the ability to digest and absorb food, mechanically damage the intestinal mucosa, etc. Too much fiber in the diet can partially block the activity of some digestive enzymes, so the absorption of nutrients from the meal is disturbed, which can ultimately cause a deficiency, especially iron, zinc and calcium because plant fibers bind to them and excrete them in the feces. For these reasons, it is always necessary to consult a doctor and nutritionist. Allergic reactions to psyllium are extremely rare.
Previous experiments and clinical studies suggest that dietary fiber with a balanced diet can contribute to achieving and maintaining body weight and prevent metabolic complications as a result of obesity, which is increased serum lipids and glucose, high blood pressure (hypertension) with the presence of indicators of inflammation. Water-soluble fiber such as psyllium affects postprandial (after meal) glucose and insulin levels in people with type 2 diabetes, has a positive effect on weight reduction and high blood pressure, suggesting a potential role for these fibers in overall health.
Studies have shown that dietary supplements in the form of psyllium help maintain body weight, regulate blood sugar and cholesterol.
Consumptionof psyllium before a meal has the effect of reducing the feeling of hunger and the desire to take food between meals and increasing the feeling of fullness (satiety) of the stomach.
Psyllium should be taken with liquid.
*Prevalence is the number of all cases of certain diseases in a certain population in a certain period. It is most often expressed as a percentage or rate.
**The metabolic syndrome is a set of metabolic disorders that increase the risk of type 2 diabetes, cardiovascular disease, stroke and obesity, and is manifested by increased cholesterol, sugar and blood levels, accumulation of fat in the abdomen (abdominal or central obesity) and increased blood pressure.
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Sandra Hrg, dipl.ing.,univ.mag.pharm.