Can Garlic Lower Your Cholesterol?

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If you are wondering how to lower cholesterol naturally, you may not be aware of how garlic benefits your cholesterol levels.

Garlic (Allium sativum) is a plant closely related to the leek and the onion. Known for its distinctive odor, it has also been designated the name “the stinking rose." Garlic has a variety of useful purposes. It is mostly known for the flavor it adds to a variety of foods. Additionally, garlic contains the chemical allicin, which has been shown to kill bacteria and fungi and alleviate certain digestive disorders.

It also lowers the clotting properties of blood. But the most notable attention garlic has received over recent years is its possible usefulness in lowering cholesterol levels.

Does Garlic Actually Work?

Garlic is one of the most widely purchased herbal supplements used to lower cholesterol levels. So, does it work? Yes and no. Most of the research studies involving both animals and humans suggest that garlic can lower cholesterol levels. In most of the studies that produced cholesterol-lowering results, about one-half gram or one gram of garlic was consumed a day. Additionally, it seemed that the garlic lowered total cholesterol and triglyceride levels by up to 20 mg/dL in humans. LDL cholesterol (“bad” cholesterol) levels were very modestly lowered (if at all) whereas HDL cholesterol (“good” cholesterol) was not affected by the administration of garlic. The cholesterol-lowering abilities of garlic appear to be dose-dependent.

That is, the more garlic you take, the lower your cholesterol will drop. In the very few studies that looked at the long-term effects of cholesterol, it appears that the cholesterol-lowering effect of garlic may be only temporary.

Additionally, there is some debate as to which form (powder, extract, oil, tablet, raw) of garlic is the best in lowering cholesterol levels.

Some studies suggest that garlic powder may have lower amounts of allicin, one of the active ingredients in garlic. This, too, remains under debate.

It is important to note that these studies are very conflicting. While there are many studies that conclude garlic works well to lower cholesterol levels, there are also other studies that conflict with this, contending garlic is ineffective in lowering cholesterol. Therefore, until more studies are performed, garlic may not be the best choice for you if you are solely relying on it to lower your cholesterol.

What Should I Know About Taking Garlic?

Most of the studies that examined the effectiveness of garlic on cholesterol used anywhere from 500 –1000 mg of cholesterol in their study. The garlic preparations vary widely, from powders used in tablets to raw garlic used in cooking.

  • Be sure to tell your healthcare provider that you are taking garlic supplements to lower your cholesterol, since they may interact with certain disease conditions or medications you are taking.
  • The most notable side effect of garlic is the presence of its persistent, distinctive odor being present on your breath and body. Some commercial preparations may boast of lowering this side effect, but you should still be aware that this undesirable side effect might occur.
  • Additionally, if you are taking any type of blood thinner (anticoagulants like Coumadin®, (warfarin) or need surgery soon, you should not take garlic without first consulting your health care provider because this may lower your ability to clot your blood.
  • Although there is not a definite limit on how much garlic you can consume a day, some studies have suggested that too much garlic may be harmful to your liver. One study concluded that doses of garlic above 0.25 g/kg and above per day may harm your liver. For instance, if you weighed 150 lbs, this would roughly equal to consuming 70 grams of garlic today. This would be equivalent to eating 18 cloves of garlic or taking over 100 commercially available tablets (1 tablet = 400 mg).


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