Dietary fiber has a much bigger role to play in health and isn’t just in the management of constipation. Several scientific studies and research now explain their role in treatment, prevention and reducing risk of obesity, heart disease, diabetes, and some cancers like colon cancer. Fiber is only found in plant sources of foods and classified as soluble, insoluble, fermentable and non-fermentable based on how it is digested in our gut.
If you didn’t know, fiber can only be found in foods and is not available in isolation like Metamucil powder or capsules. Fiber-rich foods include fruits, vegetables and whole grains. Eating foods containing fiber in its natural form provides fullness or satiety and leads to lower consumption of overall calories. Further, the process of chewing and biting these foods, rather than guzzling down a glass of juice, burns more calories when chewing. Other benefits of fiber-rich foods for weight loss are slowing down the speed at which food moves down the stomach and gut – which is another mechanism, keeping us full and less hungry between meals. Fiber also holds on to more water and adds to bulking and volume and is the reason its popularly used to manage constipation – adequate hydration really helps this purpose. Pro tip: it’s better to eat fresh or frozen fruits and vegetables and avoid dried fruits.
The net calories absorbed from fiber-rich foods (nutrient dense foods) are much lower than foods that do not contain fiber. Most processed foods, ultra-processed foods and beverages do not contain fiber at all, or have very little fiber making, them easy absorbable high calorie content [calorie dense foods] and favoring obesity. Natural alternatives are ideal high fiber foods for weight loss.
Fiber in a diet is a rich source of nutrition for the healthy bacteria that resides in our gut – these gut bacteria digest the fiber and break it up in to short chain fatty acids that help maintain a healthy gut microbiome. Several studies have shown that there are specific patterns on predominant gut bacteria species identified in obese versus healthy weight individuals showing that appetite, hunger and metabolism can be vastly altered and develop patterns of eating, weight gain or weight loss. This effect however isn’t sustained unless the recipient maintains the healthy eating habits .
The standard American diet is known to have around 10-15gm fiber in daily diet, while the recommended dietary fiber is 35-50gms per day. It has been noted that higher fiber diets, such as in hunter gatherer populations such as Haadza in Tanzania, have a more variety of healthy gut bacteria species that favor wellbeing and less incidence of chronic disease, while industrialized populations consume higher amounts of processed foods have lower variety of gut bacteria and a higher risk for chronic diseases and cancers.
While increasing the overnight consumption of fiber can lead to gas, bloating, cramps, etc., it is recommended to slowly increase the intake of high fiber foods and work closely with a specialized dietician.
Ideal fiber-rich foods for weight loss include:
- Vegetables: most vegetables if steamed, roasted or raw – green, leafy vegetables like broccoli, brussel sprouts, green beans, spinach, and kale
- Unprocessed whole grains: wild rice, brown rice, quinoa, millets, lentils, wheat, corn, old fashioned oat meal/overnight oats
- Fruits: apples, plums, berries and bananas
Handy tip – if foods have more than 2-4 ingredients with unrecognizable names, these are definitely processed foods. Foods that you recognize which are straight from nature and unaltered, or minimally altered, are considered whole foods and much more favorable for health benefits and maximize the benefits of fiber for weight loss/preventing weight gain.