Dietary fibre is an essential component of our diet. Our diet should contain a combination of both soluble and insoluble dietary fibres to meet our daily needs. Both types play a significant role in keeping us healthy. Insoluble fibre, on one hand, helps provide bulk to the stool. Soluble dietary fibre, on the other hand, helps maintain blood sugar and cholesterol levels, it promotes gut health by maintaining microbial balance and alleviates digestion issues like constipation, diarrhoea, acidity and heartburn.
Soluble dietary fibre is more beneficial as compared to insoluble dietary fibres. In this article, we will specifically focus on the cholesterol-lowering properties of soluble fibre. It is present in dietary sources like whole grains, beans, avocados, apple, banana, guava, plum and sweet potatoes.
High cholesterol levels are associated with an increased risk of cardiovascular disorders. Several studies have shown that the consumption of soluble dietary fibre like pectin, beta-glucan, psyllium and guar gum is beneficial for lowering elevated cholesterol levels and also to prevent the risk of cardiovascular disorders.
There are different mechanisms by which soluble fibre lowers our cholesterol. Firstly, it stimulates the excretion of bile in faeces by preventing the re-absorption of bile in our small intestine. Cholesterol is present in our body via two sources - synthesized in the liver and dietary cholesterol from the food we eat. Soluble fibre is soluble in water, forms gel-like structure and clasp the fat and cholesterol in our small intestine so that it doesn’t get absorbed in our blood. Clinical data revealed that ingestion of soluble dietary fibre results in low levels of total plasma cholesterol, low-density lipoprotein (LDL) levels, without affecting HDL levels. Another mechanism by which soluble fibre prevents the rise in cholesterol levels is by slowing down the digestion. A sudden spike in blood glucose levels contributes to the synthesis of triglycerides. Thus, dietary fibre prevents a sudden rise in post-meal blood sugar levels. This, in turn, keeps blood cholesterol profile healthy and in safe limits. Dietary fibre reduces insulin production by the pancreas, which causes a reduction in cholesterol synthesis because insulin is needed for the activation of HMG CoA reductase.
Dietary fibre is an indigestible carbohydrate. It neither gets digested nor absorbed by us. Bacterial fermentation of soluble fibre in the large intestine results in the production of short-chain fatty acids are known as acetate, propionate and butyrate. This is the third mechanism by which fibre benefits us as propionate also inhibits cholesterol synthesis in our liver.
To conclude, soluble dietary fibre is an important asset when it comes to keeping our heart healthy. It keeps blood cholesterol levels in check thereby reducing the risk of stroke and many hearts affecting diseases. As per the National Institute of Nutrition, at least 30-40 grams of dietary fibre should be consumed per day. It benefits our glucose and lipid metabolism along with keeping our digestive system and bowel movement healthy. Therefore, consume plenty of fibre-rich foods in your diet. Opting for dietary fibre supplements is also a great alternative.
P. Gunness, MJ. Gidley(2010)Mechanisms underlying the cholesterol-lowering properties of soluble dietary fibre polysaccharides. PubMed. Retrieved from www.ncbi.nlm.nih.gov/
L. Brown, B. Rosner, WW. Willett, FM. Sacks, (1999)Cholesterol-lowering effects of dietary fiber: a meta-analysis. PubMed. Retrieved from www.ncbi.nlm.nih.gov/
Narayan. Shreya, Lakshmipriya. Nagarajan, et. Al (2014)Association of dietary fiber intake with serum total cholesterol and low density lipoprotein cholesterol levels in Urban Asian-Indian adults with type 2 diabetes, Retrieved from www.ijem.in/
Ramos.Silvia C, Fonseca. Francisco A, et. al.(2011)The role of soluble fiber intake in patients under highly effective lipid-lowering therapy. Nutritional Journal. Retrieved from https://nutritionj.biomedcentral.com/Buy Now