Oatmeal for Cholesterol Lowering

Eating a bowl of oatmeal every day can start to lower your total cholesterol and LDL (or "bad") cholesterol in as little as two weeks. The secret sauce is the soluble fiber it contains, called beta-glucan. Studies show that when you eat 3 grams or more each day — about a serving and a half of oatmeal — you're likely to reap the cholesterol-lowering benefits. 

Your liver uses cholesterol to make bile. That's an acid that helps break down fat in the small intestine. After bile's job is done, your body recycles it for future use. But if you've been eating a lot of oatmeal, beta-glucan essentially shuts this recycling program down. It absorbs water in your gut and forms a gel that stops it from recovering bile. Your liver has to pull cholesterol from your bloodstream to make more bile, which lowers your cholesterol. 

Bacteria in the digestive tract break down natural compounds in oats, resulting in ferulic and dihydroferulic acids. These may help your body handle cholesterol better. 

About 3 grams of oat beta-glucan a day may lower LDL cholesterol by roughly 5%, with some studies showing as much as 10%, often within a few weeks. Look for soluble fiber on the nutrition label. One study found that it took about three-quarters of a cup of dry oats to get these effects. But not everyone gets the same results. Those with the highest cholesterol to begin with and people with diabetes may reap the most rewards. To maintain the results, oats likely need to become a regular part of your diet.

Some of oatmeal's benefits happen as this food is broken down in your gut.  Instant oatmeal is partially broken down during processing, so you might not get the same effects. Steel-cut and rolled oats are not heavily processed and may be more likely to bring heart-health benefits. That said, quick and instant oats aren't automatically bad. Look for a brand that lists "whole grain oats" or "whole grain rolled oats" as the first ingredient. And if you've got a few choices, choose one with more soluble fiber. Skip the ones with lots of added sugar and flavors. 

Stovetop. Bring 1 cup liquid (milk, water, or a mix)  to a boil. Stir in ½ cup of oats and a pinch of salt. Reduce heat to medium and cook uncovered for 5 minutes, stirring occasionally.  
Microwave. Heat 1 cup liquid, ½ cup oats, and a pinch of salt for 2½ to 3 minutes. 
Oven. Combine 2 cups oats, 1⅔ cup liquid, and a few dashes of salt in a baking dish. Bake at 350 for 35 minutes. 
Instant Pot. Combine 1 cup oats, 1 cup milk, and 1 cup water. Close lid, set valve to "sealing," and cook at high pressure for 2 minutes. Overnight. Combine 1 cup oats with 1 cup liquid. Cover and refrigerate overnight. 

What you toss into that bowl of oatmeal can make it or break it. Try these options before reaching for sugar, maple syrup, or high-calorie granola. Berries bring natural, low-sugar sweetness and antioxidants. Apple or banana slices provide sweetness and extra fiber. Nuts and chia or flax seeds offer crunch and healthy fats. Nut butters, tahini, and Greek yogurt add protein. Cinnamon, nutmeg, ginger, and cardamom add a bit of sweetness without sugar.

Like oatmeal, oat bran also contains beta-glucan, and studies show oat bran may help lower cholesterol, too. You can find it in breads and high-fiber cereals. You can also buy oat bran and bake with it, add it to smoothies, sprinkle it over yogurt, salad, or cereal, or cook it on the stovetop to make a hot, creamy breakfast porridge. In whatever form you purchase it, check the label for a high soluble fiber content. 

Oat milk can help lower cholesterol, too, as long as it has beta-glucan in it. A randomized controlled clinical trial that included 207 adults with high LDL cholesterol found that those who drank three servings of oat milk per day, for a daily total of 3 grams of beta-glucan, for four weeks saw their LDL cholesterol drop by about 6% and their heart disease risk go down by 8%. But the beta-glucan content in many oat milks may not come near 1 gram per serving. Check the soluble fiber on the label. 

Oatmeal, oat bran, and oat milk aren't the only way to get cholesterol-lowering beta-glucan. You can also find it in whole-oat cereals, muesli, breads or muffins made with whole-oat flour or oat bran, and some foods fortified with oat beta-glucan. Some oat protein drinks and powders may count, too. But processing often removes a lot of the beta-glucan. The trick with any oat-containing product is to look at the soluble fiber content and aim for 3 grams per day

Studies finding that a daily dose of oat beta-glucan can lower cholesterol usually get those results within two to four weeks. You may see your cholesterol fall, though at a slower pace, for up to eight weeks. You'll likely need to continue to get oat beta-glucan every day to maintain the results. 

Keep these two things in mind: First, a sudden increase in soluble fiber might be a bit of a shock to the system — at least at first. While your gut adjusts, you might have some gas, bloating, a stomachache, and possibly diarrhea. Start out slow. Add 1 to 2 grams of soluble fiber a day to start, and then gradually work up to 3 grams. Second, dietary changes to improve heart health should enhance your medication plan, not replace it. Keep taking your meds as directed unless your doctor tells you otherwise.