Foods High in Choline and the Mediterranean Diet: Do They Cause Heart Disease?

Eggs
Credit: Junko Kimura / Staff/ Getty

Choline is a water-soluble micronutrient that helps our system function properly. It helps maintain a healthy metabolism and normal brain development. Foods high in choline include egg yolks, liver, red meat, peanuts and wheat germ.

Heart disease is a major cause of death in the U.S. Researchers have found that excessive intake of foods high in choline may increase the levels of trimethylamine-N-oxide (TMAO), which causes blood clots and increases the risk of heart disease. So, you should prevent excess consumption of foods high in choline.

Mediterranean Diet and Foods High in Choline

Consuming a Mediterranean diet can lower the risk of heart disease and stroke. For many years, physicians and researchers have been emphasizing the importance of the Mediterranean diet.

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Dr. Stanley Hazen from the Cleveland Clinic recommends a Mediterranean or a plant-based diet for people with high levels of gut metabolites. This diet includes consuming fresh fruits, nuts, green veggies, and healthy oils. It limits the intake of red meat and high-fat dairy products, such as whole milk, egg yolk, cream cheese, and butter. However, you can consume these in moderation. The Mediterranean diet includes foods high in choline, such as cruciferous veggies and limited amounts of eggs and dairy.

Researchers at the Cleveland Clinic found that the Mediterranean diet alters the activity of gut microbes. The animal study found that compounds from grape seed oils, cold-pressed extra virgin olive oils, and balsamic vinegar prevent gut microbes from turning unhealthy foods into metabolic by-products.

Choline Is Essential

Is choline a vitamin? Technically, choline isn’t a vitamin, but it is considered part of the B-complex vitamins.

Choline, as well as betaine, which is a metabolite of choline, play an important role in reducing inflammation. Both these compounds reduce plasma homocysteine levels. High levels of homocysteine are linked to increased heart disease. It is an amino acid mainly found in meat.

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Can Choline Cause Stroke?

Choline feeds gut bacteria. The bacteria make a compound which results in clot-forming, sticky blood. Consequently, this may lead to stroke or a heart attack.

Dr. Hazen and his research team found that the compounds present in animal products increase the levels of TMAO. TMAO makes the platelets form blood clots. The results of the study were published in Circulation.

Gut microbes convert choline and carnitine into trimethylamine (TMA). Host enzymes convert TMA into a metabolite called trimethylamine N-oxide (TMAO). TMAO increases the risk of heart disease in humans and accelerates atherosclerosis in animals.

Dr. Hazen says that there is a link between many chronic diseases like obesity, atherosclerosis, and diabetes with gut microbes. To prevent atherosclerosis, you should target gut microbes. It is possible to prevent the diet-induced heart disease that starts from the gut.

Research Findings on Choline

The previous approach to preventing heart disease inhibited the host enzymes, which convert TMA into TMAO. However, this was found to damage the liver and cause an unhealthy build-up of TMA. The better approach was to target the gut microbes and prevent the formation of TMA.

According to the American Heart Association’s publication, excess intake of choline raises both levels of the bacteria-produced compound, trimethylamine N-oxide (TMAO), and the clumping of platelets to form clots. High levels of TMAO are associated with a greater risk of heart attack and stroke.

However, in the study, it was observed that even after taking choline supplements, vegetarians and vegans had lower amounts of choline and TMAO than their non-vegetarian counterparts. So, while you cannot conclude if choline is responsible for stroke, it is better to consume these foods in moderation, or focus on eating more vegetarian foods. Also, we cannot deprive ourselves of this micronutrient because it has many other health benefits related to brain development, heart health, reducing inflammation, and so on.

Having an oral choline supplement for more than two months can increase the trimethylamine N-oxide (TMAO) by 10 times, especially if you eat red meat regularly. You should take choline supplements only if prescribed by your doctor.

5 Foods High in Choline

According to a study published in The National Academies, adequate choline intake reduces the risk of cardiovascular disease, dementia, and cancer.

The recommended daily intake of choline is yet not established. But adequate intake (AI) is 425 milligrams per day for women, and for adult men, it is 550 milligrams a day.

These are some of the foods high in choline.

Eggs

Egg yolk contains most of the choline compared to the whites. A cup of chopped eggs provides 399 milligrams of choline.

Fish eggs also provide good amounts of choline. They provide nine percent of the adequate intake per tablespoon.

Beef Liver

A 100-gram serving of beef liver provides 418 milligrams of choline.

Cauliflower

A cup of raw cauliflower contains 47.4 milligrams of choline. A cup of cooked broccoli provides five percent of the adequate intake.

Mushrooms

A cup of cooked shiitake mushrooms contains 57.6 milligrams of choline.

Oysters and Cod Fish

A three-ounce serving of oysters contains 85.9 milligrams of choline. The same serving of cod contains 67.8 milligrams.

The Final Word on Choline

To conclude, we can say that choline and betaine are important for many aspects of our health. Consuming choline-rich foods in excess along with supplements may increase TMAO levels and could increase the risk of heart disease. However, this has not been scientifically proven yet.

On the other hand, choline is just as essential for us as vitamin B12, folate, iron, calcium, and vitamin C. So, we should include choline-rich foods in our daily diet, as long as we do not exceed their intake.


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Sources:

Fox, M., “Bacteria May be Reason Some Foods Cause Heart Disease, Stroke,” NBC News, April 24, 2017;
http://www.nbcnews.com/health/health-news/here-s-one-way-meat-eggs-can-kill-you-n750416.

“Top 10 Foods Highest in Choline,” Healthaliciousness; https://www.healthaliciousness.com/articles/high-choline-foods.php, last accessed April 26, 2017.

Lozovschi, A., “Choline And Bacteria May Be Culprit Behind Stroke And Heart Disease,” Tech Times, April, 25, 2017; http://www.techtimes.com/articles/205885/20170425/choline-and-bacteria-may-be-culprit-behind-stroke-and-heart-disease.htm, last accessed April 27, 2017.

Zeizel, H., “Is there a new component of the Mediterranean diet that reduces inflammation?” The American Journal of Clinical Nutrition, February 2008; 87(2): 277-278; http://ajcn.nutrition.org/content/87/2/277.full, last accessed April 27, 2017

“Heart Disease and Homocysteine,” WebMD, September 14, 2016; http://www.webmd.com/heart-disease/guide/homocysteine-risk, last accessed April 27, 2017