Here are four simple facts:

1. Around 71 million Americans have high LDL cholesterol.

2. Elevated levels of bad LDL cholesterol fuel heart disease, which leads to around 371,000 deaths annually.

3. Americans get far too little fiber in their diet. If they just added just one-third of an ounce of fiber a day to their diet, they could lower their risk of fatal heart disease by 17%.

4. Four ounces of raw oats contain 4 grams of fiber.

Speaking of oats, a study in the journal Nature Communications looked at how people with metabolic syndrome (elevated blood pressure, glucose levels, and lipids along with being overweight) could reduce their LDL cholesterol levels quickly.

The answer: oatmeal.

For two days, participants ate nothing but a total of 10.5 ounces of oatmeal cooked in water with some added fruit and vegetables, divided into three servings. Their LDL cholesterol immediately fell by 10% — and stayed that way for the next six months.

How could a short-term fiber bomb produce such positive-lasting effects?

The researchers found that it caused significant improvements in gut health, upgrading the balance of beneficial microbes, improving the integrity of the intestine's lining, and changing how the body metabolized glucose and fat.

After you do a two-day oat-fest, keep fiber in your diet with the recipes in my book "The What to Eat When Cookbook," and for more heart-loving ways to live longer and healthier, check out "The Great Age Reboot."

And ask your doctor about getting therapeutic plasma exchange.