Resistant Starch Is the Carb That Goes the Extra Mile in Your Diet

For some people, “carb” is still viewed as a dirty four-letter word. We’ve heard time and time again how “bad” carbs are for us, and that idea can be hard to ditch for some. However, this concept largely applies only if you’re eating too many processed carbs, such as white bread and sugary candies.

Not all carbohydrates are created equal—and that is a good thing for your health. Whole grains supply plenty of must-have nutrients for optimal well-being and performance, while fiber helps with everything from keeping us regular to improving cholesterol numbers for a healthier ticker. Besides, hungry runners are always down for more carbs to fuel their training.

And now, emerging research suggests that a unique kind of carbohydrate could be key to helping counter weight gain and support the gut: resistant starch.

What sets resistant starch apart is that unlike other types of starchy carbs, which break down into simple sugars in your small intestine (the place where most food is processed), resistant starch—aptly named because it “resists” digestion—stays intact until it reaches your large intestine (colon). This is why it’s technically classified as a dietary fiber.

Certain populations and cultures have benefited from resistant starches for a long, long time. Now, modern research has linked resistant starch to some legit benefits. Here’s why runners are best served not being resistant to eating more of the stuff.

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Why You Should Eat More Resistant Starch

So far, the research on resistant starch is promising, and it may help in the fight against various health woes including diabetes, certain cancers, and even obesity. The reason resistant starch seems to be so uniquely healthy is because of the way it’s digested, namely by bacteria in your colon. In this way, resistant starch acts as a prebiotic in that beneficial bacteria feed on it to increase their population numbers to improve your gut microbiome, which, in turn, may benefit your digestive and immune health. This is particularly important during stretches of intense training.

Also, when the critters in your digestive track nibble on resistant starch, it results in the production of short-chain fatty acids such as butyrate, which themselves may offer up perks including regulating metabolism and immunity. All these microbiome benefits come minus the lofty price tag of kombucha, for example.

More and more research suggests sneaking resistant starch into your diet can also have some weight-loss benefits, if that is your goal. For instance, studies—including this one and this one found—that boosting resistant starch intake can alter levels of hormones involved in appetite regulation, such as leptin, in a way that keeps you feeling more satiated throughout the day, an important part of curbing overeating.

In a Nutrition Journal study, researchers cooked a series of four pancake breakfasts for 70 women. The pancakes were made from ordinary starch, starch plus whey protein, resistant starch, and resistant starch with whey protein. After the subject ate pancakes containing resistant starch plus protein, they experienced an uptick in fat burning and feelings of fullness, compared to all of the other types of pancakes. This hints at the power of teaming up resistant starch and protein for weight control.

One way that resistant starch can turn up the fat-burning furnace is by increasing the number of calories we burn via the “thermic effect of food.” The thermic effect of food (TEF) is the amount of energy it takes to break down a food molecule. For resistant starch, the body may use more energy to process this type of carbohydrate when compared to regular starches. Plus, since resistant starch is not digested, it does not contribute calories to the food it is in.

Resistant starch also improves insulin sensitivity and lowers post-meal blood sugar numbers by slowing down digestion, compared to eating fast-digesting refined or sugary carbs. This can lower the risk for type 2 diabetes, a condition that impacts more than 30 million Americans.

There’s also some evidence that eating resistant starch can help counteract the negative effects of eating a lot of red meat concerning colorectal cancer risk—good news for those who site burgers as their favorite way to get protein after a workout.

But, we still need to see more larger-scale studies using amounts of resistant starch that are feasible in a typical diet to be able to say that it certainly can benefit your waistline.

How to Eat More Resistant Starch

Despite the impressive health benefits being attributed to resistant starch, a report in the Journal of Nutrition determined that very few Americans eat the suggested 10 to 15 grams a day (there’s no formal recommendation for the intake of resistant starch).

Just be warned that if your current diet is low in resistant starch and fiber in general, it’s a good idea to gradually up your intake to limit uncomfortable digestive woes, like bloating and gas.

Here are seven foods to add to your diet to eat more of this overachieving carb.

1. Muesli

As a general rule, starchy foods have more resistant starch when they are raw—cooking breaks up the structure of the starch. So, raw oats contain more of the resistant starch called amylose than cooked ones do, which makes muesli, a European-inspired cereal typically made with unheated oats, nuts, and dried fruits, a good way to kick off the day. Serve it over yogurt or soak it overnight in milk.

2. Green bananas

Bananas with a green-tinged skin can contain up to 80 percent more resistant starch than the fully-ripened fruit does, where the resistant starch has been converted to sugars. So try blending less-sweet unripened green bananas into your postrun smoothies or slice and scatter on yogurt or cereal. Here’s another tip: Try using banana or plantain flour (made by grinding up dried, unripe fruit) in your baking.

3. Potatoes

Consider cooking potatoes ahead of time and letting them cool in the fridge. When cooked and then cooled for about 24 hours, the digestible amylopectin starches in potatoes convert into the hardened resistant starch called amylose allowing for fewer carbs to be digested. Potato salad, anyone?

4. Rice

Rice naturally has some resistant starch, but it loses its structure during the cooking process. But let cooked rice cool and some of the carbs revert back to the resistant form. Translation: chilled brown rice might be healthier for you than just cooked. If you’re wondering how long you should let your rice cool down, a study found 24 hours to be the most effective.

So try making big batches of the grains ahead of time and then using it up during the week for in stir-fry recipes, grain bowls, and lunch salads. The heating-cooling method can also be used for other grain-based products, like pasta, to bump up resistant starch numbers. It remains to be seen what level of resistant starch is retained if you reheat previously cooled cooked grains and potatoes.

5. Cashews

Among nuts, it’s thought that cashews lead the way in the resistant starch category. So enjoy them as an out-of-hand snack or toss the buttery nuts onto oatmeal, yogurt and salads.

6. Beans

Various beans including pinto, black, and chickpeas are a natural source of resistant starch, about 3 to 5 grams in 100 grams cooked. Allowing cooked legumes to cool in the refrigerator for a few hours before eating will increase the resistant starch content.

7. Barley

Barley is another whole grain that contains resistant starch making it a good addition to hearty winter soups and grain-based salads. Whole grain varieties of foods tend to contain higher amounts of resistant starch than “white” versions of these foods.