Written by Phoi Yan Yin
Cholesterol. What a fear-inducing word, when it really shouldn’t be. I know some of you out there would dread health check-ups or blood tests lest you happen to discover that your cholesterol levels are sky-high. You know that your GP will then tell you to reduce cholesterol levels by “watching your diet” and “avoiding fatty foods, eggs, and seafood”, or horrors of all horrors…“do more exercise”. This advice will then be finished off with a warning: “If not, I’m going to start you on some meds next time you come in!”
This is how you let disease fester beneath the surface and go unnoticed for years until sometimes, it gets too late.
Darn it, I gotta start cutting out all my favorite foods, you think. Right?
Wrong. What if I told you, that there were foods that you can start eating more of to reduce your cholesterol levels? It’s not just about removing foods from your lives, my dear readers, it’s about adding some others in.
Now don’t say dietitians are the bringer of bad news. I’m telling you this straight out—YES, there are foods you can eat that will reduce your cholesterol levels. And this is not just based on research carried out on animals or a single stand-alone trial on humans. These recommendations are based on reviews of multiple studies carried out on humans. Of course, because these studies vary in design, population, type, and amount of the food being investigated, there’s always a need for larger numbers of longer-term studies. However, I would say that the case for these foods being capable of reducing cholesterol levels, specifically LDL-cholesterol, is pretty strong. Wait—What? What’s LDL-cholesterol?
Alright. First things first. Let’s clarify the basics of this topic.
What is cholesterol?
Cholesterol is a fatty substance that is transported around our body in our blood. Our body produces most of the cholesterol in our body, while the rest comes from the foods we consume. Contrary to what you may think, cholesterol plays important role in our body and we cannot do without it. It is a part of our cell walls and is involved in the formation of bile acids and hormones.
However, how cholesterol is packaged in our body plays a crucial role in our health. Cholesterol is carried around our body by lipoproteins (imagine them as vehicles in your bloodstream). They include low-density lipoproteins (LDL) and high-density lipoproteins (HDL), which makes LDL- and HDL-cholesterol, respectively!
LDL-cholesterol is known to be bad, because, in excess, it accumulates and clogs up arteries, causing diseases like heart disease and stroke. On the other hand, HDL-cholesterol is known to be good as it prevents cholesterol build-up within our arteries. Total cholesterol is a combination of both LDL- and HDL-cholesterols. At times, people get unnecessarily alarmed at a high total cholesterol reading, when it could be driven up by high HDL-cholesterol levels. Therefore, it’s always important to look at the cholesterol readings individually and focus on reducing LDL-cholesterol levels.
So remember, when doctors or dietitians talk about the need to “reduce cholesterol levels”, what we actually mean is reducing LDL-cholesterol levels. Now, let’s move on to my top 5 foods that are scientifically proven to reduce cholesterol levels.
1. Almonds
Almonds are high in mono- and polyunsaturated fatty acids, vitamin E (an antioxidant), and fibre, which are factors that maintain healthy blood vessels. In a review of studies, it was found that consuming 45 grams of almonds a day led to reductions in LDL-cholesterol levels in a dose-dependent relationship. What’s more, replacing saturated fats (found in butter, animal skins, palm oil, coconut milk, and chocolate) with almonds adds to the effect and further reduces LDL-cholesterol levels.
In fact, these benefits extend beyond just almonds. A systematic review of 2582 participants found that tree nut consumption lowers total cholesterol and LDL-cholesterol, thus drawing the link between nut intake and reduced risk of heart disease. Tree nuts include walnuts, pistachios, macadamia nuts, pecans, cashews, almonds, hazelnuts, and Brazil nuts. They found greater effects on LDL-cholesterol with consumption of more than 60 grams a day, regardless of nut type. Of course, these nuts should be raw or baked, and not roasted in palm oil or coated with sugar.
2. Oats
A review in 2016 observed the effect of oats on LDL-cholesterol in 58 human trials. Most of the participants were in their middle age and two-thirds of the studies included people with high cholesterol. There is a substance in oats called beta-glucan, that improves cholesterol levels by encouraging the excretion of bile acids from the body. As bile acids are made of cholesterol, this helps reduce cholesterol levels in the body.
The dose of oat beta-glucan studied ranged from 0.9-10.3g/day, and the studies were carried out for a duration of 3 to 12 weeks. With a median dose of 3.5g/day and duration of 6 weeks, a significant reduction of LDL-cholesterol by 4.2% was observed. The review revealed that consuming higher doses of oat beta-glucan led to a greater reduction in LDL-cholesterol levels. Furthermore, it was found that the higher your baseline LDL-cholesterol level, the greater your LDL-cholesterol will reduce if you start consuming oats.
If you’re wondering what 3.5 grams of oat beta-glucan translates to, that will be about 1.5 cups of cooked oatmeal, which really isn’t too much to ask. Check out Elvis Presley’s Overnight Oats for a quick and tasty way to get oats into your diet! Trust me, it’s delicious.
3. Barley
Barley contains fibre, phytochemicals, vitamins, and minerals. However, the substance in it shown to largely contribute to its health benefits would be the same as oats—beta-glucan!
A systematic review of 14 studies found that median doses of 6.5-6.9 grams of barley beta-glucan a day for a rough duration of 4 weeks reduced LDL-cholesterol levels significantly. This would be equivalent to approximately 2.5 cups of cooked pearl barley.
While this may seem like quite a bit to consume every day, you can always include some in the form of a barley drink, which will be both a tasty and a healthy treat. Remember though, you have to eat the barley too! Otherwise, they are a great addition in small amounts to Chinese boiled soups, western-styled stews (they taste great in stewed lamb shanks!) or even Chinese desserts.
4. Flaxseed
Also known as linseed, it is a great source of omega-3 polyunsaturated fatty acid ALA and fibre (it is 29% fibre! Contained mainly in the hull). It has been shown to reduce LDL-cholesterol by 4-10% in patients with high cholesterol and 9-18% in people with normal cholesterol levels. Ground flaxseed of 30-40 grams a day has been shown to be beneficial. Grinding flaxseeds help improve the absorption of their nutrients. After grinding, you can simply sprinkle it over your breakfast cereal, atop your sandwiches, or even on rice. They also work great in stews or stir-fries, as they get mixed into the sauce.
Mechanisms by which it reduces cholesterol levels may be through increasing satiety to reduce caloric intake and increasing removal of cholesterol through faeces. The presence of fibre also produces short chain fatty acids in the large intestine that influences fat and cholesterol production and breakdown.
5. Green tea and black tea
A Cochrane review was conducted to determine the effects of green and black tea consumption on heart disease prevention. For those of you who may not be familiar, Cochrane reviews are of very high quality. This review included 11 randomised-controlled trials of at least three months on healthy adults or those at high risk of cardiovascular disease. The trials included varying types and amounts of green and black tea consumption, including capsules, tablets, and actual tea.
It found that black tea consumption reduced LDL-cholesterol while green tea consumption reduced total and LDL-cholesterol. The mechanisms by which these teas reduce heart disease risk may be due to its high levels of polyphenols, especially flavonoids. They improve blood vessel health through reducing oxidative stress, platelet inhibition, and exerting anti-inflammatory effects. These findings indicate that green and black tea consumption may have positive effects on heart disease risk factors.
These are the 5 foods that have been proven by science to reduce cholesterol levels, specifically the “bad” LDL-cholesterol in your body. As with all scientific recommendations, they become stronger with the same results being achieved in more long-term studies on a greater variety of populations. For now, though, the science is pretty strong with the foods listed above.
Also, if you notice, most of the foods above (with the exception of tea), contain fibre, which has been shown to reduce your risk of disease too. Check out my other post on how to easily get enough fibre in your diet every day.
Before I end this post, I would just like to highlight that your entire dietary pattern, or what you eat every day, matters. So, no matter how much of the above foods you eat, it’s not going to “offset” the ill-effects of an uncontrolled diet!
This article is first published at The Thoughtful Dietitian
ABOUT THE AUTHOR
Yan Yin is an Accredited Practicing Dietitian. She is the founder of The Thoughtful Dietitian, where she provides dietetic services such as nutrition consultations, health writing, and recipe development.
References
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