Dietary Fibre and Metabolic Syndrome
9th January, 2016
A Natural Approach Backed Up by Science
Metabolic Syndrome is not an actual disease. It is a group of risk factors that occur together in the same person. A person has “Metabolic Syndrome” if they have any three or more of the following conditions:
- Central or abdominal obesity – excess fat in and around the stomach or abdomen
- High blood pressure (hypertension)
- High blood triglycerides (Cholesterol)
- Low levels of high density lipoproteins (HDL) – the ‘good’ cholesterol
- Insulin resistance
- Metabolic syndrome increases the risk of developing Cardiovascular Disease and Type 2 Diabetes, so it’s increasing incidence in Australia and worldwide is a cause for concern.
Poor diet and lifestyle choices have been identified as a primary cause of Metabolic Syndrome. However there is some very strong evidence emerging for the beneficial role that dietary fibre plays in helping to manage this group of conditions – a relatively simple fix!
Dietary fibre is defined as “the edible parts of plants…that resist digestion and absorption in the small intestine, with complete or partial fermentation in the large intestine”1. In other words, they pass through our intestines almost untouched, helping to facilitate the process of digestion by influencing the absorption and transit time of the foods that we eat.
There are two different types of dietary fibre: insoluble and soluble.
Insoluble fibre refers to those types of plant fibres that act like a broom in the intestines. They attract water to help provide bulk to and soften the stool making it easier to pass. Insoluble fibre may have a role to play in maintaining the health of the good bacteria in our small intestines as well, further enhancing the digestive process.
Soluble fibre retains water to create a gel like substance. This increases the thickness of the stomach and intestinal contents, slowing down stomach emptying and nutrient absorption and providing a feeling of fullness after we eat.
Each type of fibre has its own individual benefits in relation to the management of the conditions of Metabolic Syndrome but the general consensus is that a mixture of each type in the diet is optimal as most foods contain a combination of both in different quantities. Good food sources of fibre include fruits and vegetables; however the best sources of both types of fibre include whole grains (particularly oats and rye but also wheat and brown rice) and legumes (beans, lentils etc). What is most important is that these grains need to be consumed in their unrefined state. This means that your best choice at the supermarket when keeping fibre in mind is to go for the brown stuff! Whole wheat pasta, brown rice, and whole grain breads contain much more dietary fibre than their white counterparts. In fact, a meta-analysis of 6 population studies has shown that increasing your whole grain intake by as little as two servings per day may decrease your risk of developing Type 2 Diabetes by as much as 21% due to its high fibre content1.
Fibre may help to regulate and maintain healthy blood sugar levels by bulking and thickening up the foods in the stomach and intestines, thereby slowing down the digestion and absorption of sugars from the foods you have consumed. This creates a “slow release” mechanism for the delivery of sugar into the bloodstream, minimising the negative effects of blood sugar spikes such as high insulin levels, lowered insulin sensitivity and energy crashes.3
Healthy cholesterol, HDL and LDL levels are thought to be maintained by the ability of fibre to increase bowel regularity. The liver will naturally help to regulate cholesterol levels by adding it to bile which is secreted into the small intestine, incorporated into the stool and later excreted when you go to the toilet. By making defecation more regular, fibre may help to reduce and then regulate healthy cholesterol levels in the body1.
Fibre exerts its beneficial effects on obesity by promoting a feeling of fullness or satiety. It helps to slow down the digestion and movement of food through the stomach and intestines, thereby helping you feel fuller sooner and for longer. This action has shown in numerous long term clinical trials involving high numbers of participants to contribute to weight loss and reduce the chance of weight gain3.
The recommended daily intake of fibre for adults is around 30gms daily to maintain healthy digestive function; however, according to a survey done in Australia in 2016 by the Australian Bureau of Statistics, Australians are falling extremely short of getting this amount each day. Less than 4% of us are meeting the recommended guidelines for the consumption of fruit, vegetables and legumes each day. Two thirds of recommended grain serves are coming from highly refined grains rather than the wholemeal, higher fibre sources. And one third of the fruit serves we are consuming come from juice which contains little to no fibre at all2.
It seems almost absurd to think that one of the most concerning metabolic conditions facing us today can be managed by some very simple and for some of us relatively small changes to our diets. Diseases of lifestyle kill more Australians each year than anything else and some small, simple steps may be all it takes to slow the progression of the conditions associated with Metabolic Syndrome. For more information, take some time to chat to your Naturopath or other Healthcare Professional and take control of your health!
1 https://www.ncbi.nlm.nih.gov/pmc/articles/ PMC2903728/ Gastroenterology 2010 Jan; 138(1): 65–72.Dietary Fiber Supplements: Effects in Obesity and Metabolic Syndrome and Relationship to Gastrointestinal Functions. Papathanasopoulos, A. M.D. and Camilleri, M. M.D.
3 Journal of Nutritional Biochemistry 2008; 19: 71-84. Effects of dietary fibres on disturbances clustered in the metabolic syndrome. Galisteo, M, Duarte, J and Zarzuelo, A