In the past couple of months, I have come across posts or messages on social media and elsewhere regarding one of the most sought-after topics – CHOLESTEROL. There are all kinds of posts/articles floating around – some say cholesterol is no longer bad while some say it increases the risk for several heart ailments and diabetes. All this prompted me to write this piece to help us understand and get a better perspective of this issue.
Let’s first begin by understanding few basic details about cholesterol.
What exactly is cholesterol?
Cholesterol is a type of fat which is produced in the body. Liver is the major organ involved in producing it. In addition to the liver, it is also produced to some extent in the intestine, adrenal gland and the reproductive tissue.
What does cholesterol do in our body?
Cholesterol is essential for our body to perform several functions. Firstly, every cell in our body (we have over millions of cells) is made up of cholesterol. It maintains the fluidity or viscosity of the cell membrane which is crucial for all the metabolic (chemical) reactions concerned with the cell. Secondly, cholesterol is essential for the formation of key chemicals in our body – bile acids (required for digestion of fat), steroid hormones (estrogen, progesterone, testosterone, glucocorticoids, aldosterone) and vitamin D. Some of these hormones are important for reproductive and sexual function while others are associated with controlling metabolism of nutrients, inflammation, immune function and water balance. Vitamin D is not only a nutrient but an essential hormone required for a variety of functions.
For the smooth functioning of our body, every cell should have sufficient supply of cholesterol.
How does cholesterol reach every cell?
Cholesterol is packed in lipoproteins called LDL and HDL. Of these, LDL carries the cholesterol to various parts of the body and delivers it to the cells. Cells have something known as LDL receptor present on their surface. These receptors act as a door to allow LDL in to the cell.
If cholesterol has so many unique attributes that are beneficial for health then, why is it that cholesterol is often projected in bad light?
Cholesterol is useful for the body when it is present in certain specific amounts. Above or below this amount, it can be harmful for the body. Most of us would be aware that high blood levels of LDL-cholesterol (LDL-c) and low levels of HDL-cholesterol (HDL-c) increase the risk of several diseases.
As mentioned earlier, LDL delivers the cholesterol to the cells. If the cell already has sufficient cholesterol then, the cholesterol (LDL-c) circulates in the blood. This is can be detected when you undergo a blood test. When higher amounts of LDL-c circulates in the blood, they can get deposited in the blood vessels (arteries) thus obstructing the blood flow and damaging the arteries. This can cause increased blood pressure (hypertension) and a variety of heart ailments such as atherosclerosis, heart attack, stroke, deep vein thrombosis and others.
How can we keep the cholesterol (LDL-c) levels under check?
Our body produces approximately 1g/d of cholesterol. On an average, we consume approximately 0.3 g/d of cholesterol. LDL-c levels (the carrier of cholesterol) can increase if – (i) the cholesterol production in the body increases and/or (ii) we consume more cholesterol from the foods and/or (iii) cholesterol is unable to enter the cells (decreased LDL receptor levels).
People may have high LDL-c levels due to certain lifestyle factors (such as sedentary lifestyle, obesity, high fat diet) or genetic issues. In both the cases, most common medical management is the use of statins. Statins are therapeutic agents (medicines) which block the production of cholesterol in the body. Besides the medical management, there are simple dietary modifications that can control your cholesterol levels.
Dietary Approaches to Control Blood Cholesterol (LDL-c) Levels
Use of soluble fibre – Normally, bile salts are reabsorbed in the intestine and sent back to the liver. Soluble fibre binds bile salts (bile is synthesized from cholesterol) and helps in their excretion from the body. In this way cholesterol can be excreted from the body. Soluble fiber is present in – oats, apple, guava, figs, banana, dried dates, papaya, raisins, sapota (chickoo), carrot, sweet potato, almonds, garden cress seeds, gingelly seeds (til), peas, lady’s finger, pumpkin, baby corn, cluster beans, broad beans, brinjal, drumstick leaves, colocasia leaves, amaranth leaves, dals, legumes (rajmah, soyabean, lentil, chick pea), barley and bajra.
Plant sterols – They block the absorption of cholesterol obtained from the food. Plant sterols are found in following grains/seeds/oils – peas, lentil, chick pea, sesame, buck wheat, mustard, flaxseed, pumpkin, millets, quinoa and rajmah.
Soy protein – Reports suggest that soy decreases cholesterol production in the body and possibly increases the entry of cholesterol in to the cells via LDL receptor (this will lower LDL c in the blood).
Almonds – They contain mono unsaturated fatty acids (MUFA), plant sterols, fiber and other healthy phytochemicals. All of them help in lowering LDL-c levels.
Besides these, you may limit the consumption of cholesterol-rich and saturated fat-rich foods – beef, pork, liver, other organ meats, whole milk, cheese, eggs, butter, margarine, mayonnaise, fried foods, baked foods (pastries, cake, doughnuts, cookies).
Indulge in regular physical activity for at least 30 mins every day. Exercise helps increase your HDL-c levels. HDL-c carries the excess cholesterol from the cells back to the liver. In the liver, it can be either metabolized to bile acids, excreted via bile salts or used for production of various hormones. HDL-c, thus, helps in utilization of excess cholesterol and hence referred as ‘good cholesterol’.
With this elaborate discussion, I hope you are enabled to answer if cholesterol is your friend or foe. Cholesterol is essential for our bodily functions however, excess can be deleterious. So, you can make subtle changes in your lifestyle to keep your cholesterol levels within limits.
Indian Food Composition Tables (2017) National Institute of Nutrition, Indian Council of Medical Research
United States Dietary Allowances (2016) https://www.choosemyplate.gov/2015-2020-dietary-guidelines-answers-your-questions
Jenkins, D.J., Kendall, C.W., Marchie, A., Faulkner, D.A., Wong, J.M., de Souza, R., Emam, A., Parker, T.L., Vidgen, E., Trautwein, E.A. and Lapsley, K.G., 2005. Direct comparison of a dietary portfolio of cholesterol-lowering foods with a statin in hypercholesterolemic participants. The American journal of clinical nutrition, 81(2), pp.380-387.
Ryan, E., Galvin, K., O’connor, T.P., Maguire, A.R. and O’brien, N.M., 2007. Phytosterol, squalene, tocopherol content and fatty acid profile of selected seeds, grains, and legumes. Plant Foods for Human Nutrition, 62(3), pp.85-91.