That triglyceride-cholesterol problem combo, says Dr. Raja Jaber, Medical Director of Lifestyle Medicine Programs at Stony Brook Medicine, "very much implies that you have what is called insulin resistance, which is one pathway for increasing cholesterol. And that is pretty much reversible with diet and exercise."

First, the good news: What to eat more of for healthy cholesterol

"You want to add a lot of soluble fiber," says Jaber, explaining that soluble, or viscous, fibers are fibers that swell up when you eat them. "And when they do that, they trap your bile acids and prevent your cholesterol from re-entering the body. They're kind of like sponges." Some excellent sources are grains including unrefined oats -- so, steel-cut oats or oat groats (the purest, least-processed form) over rolled oats or instant oatmeal -- and barley, plus beans, which also provide plant-based protein.

Some fruits also contain soluble fiber, including apples and pears, because of their pectins, as do many vegetables, such as brussels sprouts, carrots, and eggplant. The portfolio diet recommends consuming 20 grams of viscous fiber daily.

Also important are phytosterols, or plant sterols, natural compounds found in fruits and vegetables, whole grains, and nuts and seeds -- which, says Jaber, have a hormone-like effect and are "weak cholesterol," which competes with bad cholesterol for in our small intestine, helping to manage overall levels and also lowering risk of cancer, obesity, and diabetes. The portfolio diet recommends consuming only about 2 grams daily.

Good sources of phytosterols include unprocessed (or cold-pressed) extra-virgin olive, sesame, safflower, and sunflower oils -- about 3 tablespoons of which should be consumed daily, according to the portfolio diet. Other good sources of phytosterols include most vegetables but especially asparagus and broccoli; fruits including avocado, mango, and tangerines; all beans but especially soybeans; and all nuts and seeds -- which, according to the portfolio diet, should be consumed in the amount of 45 grams (about a handful) daily. Some fortified juices and yogurts also contain phytosterols, or they can be taken in supplement form.

Further, adds Nathan, "Omega-3 fatty acids -- as found in certain types of fish such as mackerel, tuna and salmon -- can improve HDL-C, or so-called 'good cholesterol,' and lower triglycerides."

These supplements can help with cholesterol levels, too

Jaber recommends two main supplements in the fight against bad cholesterol, starting with psyllium, an excellent source of soluble fiber, from the husks of the Plantogo ovata plant's seeds. It's a bulk-forming laxative (and the main ingredient in over-the-counter remedies like Metamucil), a prebiotic, and, according to a 2017 review, can help decrease LDL (bad) cholesterol by up to 24% and total cholesterol by up to 20%.

Psyllium can be found in capsule or wafer form, or in pure powder, which can be added to juice and smoothies.

Another heart-healthy supplement to consider, says Jaber, is red yeast rice, a product of yeast grown on white rice, typically found in capsule form. It contains monacolin K, an ingredient in the statin lovastatin. "It's a natural statin," Jaber says, with several studies, including a 2019 review showing that its consumption can reduce LDL levels by 15 to 25% within six to eight weeks, finding it's effective. "And statins not only lower cholesterol, they decrease inflammation. So they have a dual role, which is why they're such good medications -- and red yeast rice does the same thing."

It also may cause similar side effects, though, including abdominal issues, headache, and dizziness, and possible liver or muscle damage. Talk to your doctor first.

Finally, says Jaber, some people have found good results with bergamot, a citrus fruit that can be taken in extract oil, supplement, or juice form. A systematic review found it brought lower total cholesterol of 12.3% to 31.3% and lower LDL of 7.6% to 40.8%. "It seems to have some effect on decreasing cholesterol, but the research is not as strong," she says. "But it is relatively safe."

Still, there is a risk of allergic reaction and increased sensitivity to sunlight, so again, talk to your doctor.

Now, the bad news: What to eat less of for healthy cholesterol

There is a trifecta to be avoided: saturated fat, refined starches, and processed foods.

"So, the big one is saturated fat," says Jaber. "People think cholesterol leads to cholesterol, but it's actually not true." Shellfish, for example, contains cholesterol, but "unless you put butter on it, because butter has saturated fat in it, it doesn't raise your cholesterol." That's because research shows that most cholesterol is made in the liver by an enzyme that's stimulated by saturated fats, not cholesterol-containing foods.

Even eggs, once shunned by folks with high cholesterol, appear to be safe -- up to one a daily basis, according to various studies, notes Harvard Health Publishing.

So where are saturated fats found? Mostly animal proteins, in the form of butter, full-fat milk, and greasy meats, including steaks. Oh, and bad news, cheese lovers: Cheese is loaded with it.

"Most people who are health conscious are not eating tons of red meat, but they're eating lots of cheese," says Jaber. But it's a huge driver of cholesterol. "It's really hard for them to let it go, but you don't have to completely stop, just understand how you can change your diet." Make eggplant parmesan with much less cheese, for example, instead of "going overboard."

Adds Nathan, "Avoidance of fried and fatty foods may also help limit trans fat, a substance that has been linked to a variety of poor health outcomes and is known to negatively impact cholesterol levels."

Another big cholesterol driver is insulin resistance, which comes from consuming too many calories that overwhelm and inflame the body. That's largely from a diet containing lots of refined starches and sugars -- think white bread, pasta, cookies, and cake -- and processed foods in general. Although, says Nathan, "The interaction between simple/processed carbohydrates and cholesterol is both complex and controversial and the science is still evolving."

Research has found that with processed foods, "regardless of what's in it, and even if it has the same composition of protein, carbs and fat as an unprocessed food, the mere act of processing and ultra-processing food seems to also drive inflammation," says Jaber.

"The best way to decrease insulin resistance is to eat an unprocessed diet, which is low in saturated fat, low in sugar, and very low in refined starches," she says.

Consider swapping refined starches with unprocessed versions -- sprouted grain bread, for example, rather than bread made from flour, as "even by taking a grain and turning it into flour, you're processing it a little bit, and your absorption is faster," Jaber explains. You may also want to try brown rice, quinoa, and steel-cut oats over white rice and instant oatmeal.

And while vegans might think they're in the clear, as removing animal proteins completely from a diet automatically means you're eating less saturated fat, take note: There are two plant sources of saturated fat -- coconut oil and palm oil -- and both are found everywhere in processed vegan foods, including in butter, cheese, and meat substitutes, as well as baked goods.

"Sometimes vegans rely a lot on a lot of starches that could be refined," she says, "and that increases insulin resistance and will raise the cholesterol."

Still, it is worthwhile to aim for a largely plant-based diet, even if you can't stick to it completely, says Jaber. "Most people, if they go on a completely plant-based diet that is unprocessed with a lot of soluble fiber, they can lower their cholesterol by nearly as much as a statin."

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