Yes, oatmeal can be good for weight loss - here's how to eat it as part of a healthy diet

oatmeal fruit nuts — Oatmeal with fruit and nuts can be a healthy breakfast if you're trying to lose weight.
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Oatmeal can help with weight loss because it contains soluble fiber, which can keep you feeling full.
Steel-cut or rolled oats are the most nutritious and filling form of oatmeal to add to your diet.
Avoid processed or instant oatmeal and don’t add too much sugar to your oats for the most health benefits.
Visit Insider’s Health Reference library for more advice.

Oat-based meals are a popular breakfast food in many countries around the world, including the US, Switzerland, and Finland, which are touted as beneficial for weight loss due to a healthy mix of fiber, complex carbs, and protein. Oatmeal is rich in nutrients like magnesium, zinc, and fiber, which can help lower cholesterol, aid in weight loss, and lead to better gut health.

“Oats help people feel full, decrease sugar spikes, and decrease insulin. Those are the properties that make you feel full so you stop eating,” says Chaim Ross, MD, a gastroenterologist at NYU Langone at Great Neck Medical.

However, not all oatmeals are equal. The difference is in the oats used to make the oatmeal.

There are several types of oatmeal, including steel-cut or Irish oats, Scottish oats, rolled or old-fashioned oats, and quick or instant oats. However, if you’re looking for the least processed forms then steel-cut and rolled oats are your ticket and also deemed healthiest.

Here are the advantages of eating oatmeal in relation to weight maintenance, along with some potential drawbacks.

Weight loss benefits of oatmeal

Oatmeal contains a healthy mixture of fiber, complex carbohydrates, and plant-based protein that makes it beneficial for weight loss. A half-cup of dry Old Fashioned Quaker Oats contains 150 calories, three grams of fat, 27 grams of carbohydrates, five grams of protein, and one gram of naturally occurring sugar. It contains four grams of dietary fiber with two grams of soluble fiber.

Here are some health and weight loss-related benefits of this nutritious meal:

Oatmeal keeps you feeling full and helps regulate bowel movements: Dietary fiber, particularly soluble fiber, softens stool, making it easier to pass. It also regulates hunger by creating a feeling of fullness. "Oats have soluble fiber, which forms a gel-like formula that can leave people feeling full," Ross says.

Oatmeal helps to keep blood sugar from spiking: Another perk of eating oatmeal is that the rolled oats version qualifies as a low glycemic index food. The glycemic index (GI) is a ranking of foods based on how much they raise blood sugar. Therefore, a low GI means that oatmeal keeps your blood sugar from spiking too high during and after meals, which may help fend off hunger longer, Ross says. Spikes in blood sugar can also cause fatigue and headaches.

Keeping your blood sugar in a healthy range, particularly for people with diabetes, may prevent long-term health complications such as heart disease. The GI of rolled oats is about 55, which, for comparison, is about 25 points lower than whole wheat bread.

Oatmeal helps control insulin: As blood sugar levels rise, the pancreas produces insulin, a hormone that helps cells absorb glucose, aka blood sugar. Foods with a low glycemic index, like oats, are digested more slowly which causes a more gradual rise in blood sugar. Because insulin allows cells to absorb blood sugar which the body converts to fat if there is too much of it, low insulin levels are associated with weight loss.

Oatmeal may help boost the immune system: One type of soluble fiber, beta-glucan, is found in oats and helps activate your infection-fighting blood cells. Staying healthy means you can be active, keep a regular exercise schedule, and either lose or maintain weight.

How to eat oatmeal for weight loss

Though oatmeal has several health benefits, people should be mindful of the potential drawbacks, Ross says. Here's what to avoid or stay mindful of when incorporating oatmeal into your diet:

Don't add too much sugar and mix-ins: It may be tempting to add some sweetness and fat to oatmeal, which by itself is generally very bland. But calories from brown sugar, butter, and syrup add up quickly, Ross says. Instead, opt for fruit. "Throwing a couple of blueberries on it is a great idea," he says. "Throwing sugar on it, not a great idea."

Pay attention to portion size: While the recommended portion size of half a cup of dry oats is healthy, oatmeal can be very caloric and too carb-heavy in high amounts, Ross says. That could interfere with weight-loss goals. However, depending on your age, height, weight and physical activity level one cup or more of oats may be ok.

Stay away from instant or flavored oats: Although the calories, fat, carbohydrates, and protein content in various oats are similar, their effects on blood sugar are not. Because instant oats are more highly processed, they have less fiber and therefore a higher glycemic index.

A well-balanced, low-fat, healthy diet should include more minimally processed foods, such as whole grains, which have low-GI values. Similarly, flavored oats should also be avoided, as they are frequently full of processed sugar that the fiber doesn't offset.

Avoid eating too much too soon: "When I recommend fiber, I tell people to start slow, ease into it," Ross says. Otherwise, your body may have a hard time processing all the fiber, which can cause bloating, constipation, and stomach pain.

People should start with oatmeal two to four times a week and work their way up to daily servings, he says. It may be beneficial to have a large glass of water with oatmeal to help move the fiber through the GI tract to reduce bloating and stomach pain.

Insider's takeaway

Oatmeal can be a nutritious and filling addition to a healthy diet. Its low glycemic index combined with soluble fiber can help with both constipation and weight loss.

Although no research directly links eating oatmeal with weight loss, studies have found it to be effective for appetite control. Its ingredients and nutritional content make it an ideal addition to a weight-loss regimen.

Those introducing oatmeal to their diet should start slowly and avoid instant and flavored oats.

"I recommend that people eat the most natural oat they can find," Ross says. "If eaten in the right portions, it can help with GI issues and weight loss. Everything in moderation."