Cholesterol is an essential building block for cells, and the body makes as much of it as it needs on its own. A diet that that causes the body to produce too much "bad" LDL cholesterol can cause plaques to form in the arteries, leading to coronary heart disease, heart attack, or stroke.

According to the National Heart, Lung, and Blood Institute, the ideal amount of LDL cholesterol in the blood is 100 milligrams per deciliter (mg/dL) or lower.

If a person's LDL level is greater than this, they might consider trying a cholesterol-lowering diet. This is especially the case if the person is at high risk for heart disease due to obesity, diabetes, or other lifestyle or hereditary factors.

Although it seems counter-intuitive, it is not the cholesterol found in foods that relates to a person's blood cholesterol level. It is the saturated and trans fats that need to be reduced.

Common themes of cholesterol-cutting diets

There are many diets available that claim to lower LDL levels. However, the nutritional plans that work best share the same important elements:

• they cut saturated and trans fat intake
• they replace foods high in cholesterol and saturated fats with unsaturated fats, fruits, vegetables, legumes, and wholegrains
• they keep serving size in check to assure a healthy daily calorie intake

Three cholesterol-cutting diets that follow these guidelines are vegan diets, Mediterranean diets, and the National Institute of Health's TLC diet.

Vegan diet

A vegan diet prohibits eating animal-based foods, including fish, meat, poultry, eggs, and dairy. Only animal-based foods contain cholesterol. For this reason, veganism is the only truly cholesterol-free diet.

While cholesterol intake does not affect LDL levels as much as saturated fat intake does, many foods that have high cholesterol content also contain a lot of saturated fat. By replacing animal-based foods with plant-based foods, people can avoid both of these LDL-raising factors at once.

However, cutting cholesterol and saturated fat intake is not the only way a vegan diet can reduce LDL levels. To make this diet especially effective, it is important that people include nutrients that actively remove LDL cholesterol from the body.

The most important of these nutrients are:

• Polyunsaturated fats. These stimulate the liver to dispose of LDL cholesterol. They can be found in natural vegetable oils, such as canola, sunflower, and safflower oils.
• Soluble fibers. These dissolve into a gel in the intestines. The gel binds to cholesterol and fats and carries them off to be removed from the body before they can be absorbed into the bloodstream. Soluble fiber is found in oat-based cereals, whole grains, barley, beans, chia seeds, and eggplant. Apples, grapes, strawberries, and citrus fruits are also rich in a kind of soluble fiber called pectin.
• Stanols and sterols. These also block cholesterol from being absorbed into the bloodstream. They can be extracted from certain plants, and are often used to fortify juices and nutrition bars. They can also be taken in supplement form.

According to the National Heart, Lung and Blood Institute, eating 5 to 10 grams (g) of soluble fiber each day can lead to a 5 percent decrease in LDL cholesterol. Within weeks, a daily intake of about 2 g of either stanols or sterols can reduce LDL by about 5 to 15 percent.

Even a vegan diet fortified with these substances can have shortfalls, though. According to a literature review, cutting all animal products from the diet increases risk for vitamin D, vitamin B-12, and zinc deficiency.

Avoiding fish, eggs, and seaweed also deprives one of omega-3s, which are especially heart-healthy polyunsaturated fats. To reduce these risks, it is recommended that people on a vegan diet include:

• vitamin B-12 fortified foods, such as soy and rice beverages and nutritional yeast - leafy vegetables cannot provide enough B-12 on their own
• vitamin D fortified foods, especially during the winter months
• plant foods rich in omega-3s, such as ground flaxseed, walnuts, canola oil, soy products, and hemp-seed based beverages
• foods rich in zinc, such as whole grains, legumes, soy products, and fortified snacks

As veganism has become more popular, many resources have become available to help develop tasty meals that fit an individual's dietary needs. A recent article in Good Housekeeping suggests a variety of creative vegan recipes.

The Vegetarian Resource Group also offer a wealth of vegan meal ideas on their website, as well as a directory of vegan and vegetarian-friendly restaurants.

Mediterranean diet

If giving up animal-based foods is too difficult, following a Mediterranean diet may be a better option. While the Mediterranean diet does not allow much red meat, dairy products, poultry, and fish are acceptable in low to moderate amounts.

The American Heart Association (AHA) explain that while there are many different versions of the Mediterranean diet, each relies on the same basic nutrients:

• olive oil in place of saturated fats
• high volume of fruits and vegetables
• high-fiber starches, such as potatoes, beans, breads, and whole-grain cereals
• nuts and seeds
• fish and poultry
• eggs, up to four times a week
• wine, in small to moderate amounts

Fatty-fish focused dishes, such as this recipe for salmon with apricots, yogurt, and pistachio sauce, are rich in omega-3 fatty acids. Because vegan diets tend to lack omega-3s, a Mediterranean diet can be more healthful than a vegan diet in this sense.

However, the Mediterranean diet also has shortfalls of its own. The biggest concern is calorie intake. Though unsaturated fats and natural starches are not unhealthful, they contain a lot of calories.

If a person doesn't think about portion size carefully, they could end up gaining more weight from a Mediterranean diet. As being overweight and obesity are also risk factors for heart disease, this would defeat the purpose of lowering one's cholesterol.

The AHA advise that more than half of the fat calories in a Mediterranean diet should come from monounsaturated fats, such as olive oil. While these are much more healthful than saturated or trans fats, they have not been shown to actively signal the liver to cut LDL levels as polyunsaturated fats can.

The TLC diet

TLC stands for "Therapeutic Lifestyle Changes," and was created by the National Institute of Health in 2005. It is still considered a very strong low-cholesterol option by health experts.

The diet pairs dietary adjustments with lifestyle changes in order to lower one's risk of heart disease as much as possible. It has fewer restrictions than a vegan diet, but it also follows a much more strict, scientific structure.

According to the TLC handbook, a person should consume the following each day:

• less than 7 percent of calories from saturated fat
• 25 to 35 percent of daily calories from total fat
• less than 200 mg of cholesterol
• a low but healthy number of calories, determined with the help of one's doctor
• an optional 2 g per day of plant stanols or sterols
• an optional 10 to 25 g per day of soluble fiber

For women, 1,000 to 1,200 daily calories are usually recommended for weight loss. For men, 1,200 to 1,600 calories are recommended.

This structure is meant to ensure that LDL levels are not only lowered, but that nutrient intake is well balanced and weight is not gained in the process.

Recipes, menu plans, and tips to make vegetables tastier can all be found in the TLC handbook. The AHA also offer an online collection of heart-healthy recipes that are compatible with the TLC diet.

Health benefits

Regardless of which diet a person chooses, making healthy nutritional changes can do more than just lower cholesterol. Cutting saturated fats and increasing the intake of fruits, vegetables, nuts, seeds, and fibers can help promote healthy vision, as well as brain, muscle, bone, and digestive system health.

Weight loss also relieves stress from the major organs and arteries and reduces the risk of developing type 2 diabetes.