Peanut butter is a popular, tasty spread.

It’s packed with essential nutrients, including vitamins, minerals, and healthy fats.

Due to its high fat content, peanut butter is calorie-dense. This is concerning for some, since excess calories may lead to weight gain over time.

However, some research suggests that peanut butter may boost weight loss when eaten in moderation (1).

This article examines how eating peanut butter affects body weight.

It’s well known that weight gain can occur when you eat more calories than you burn.

For this reason, some dieters are wary of peanut butter because it’s high in fat and calories.

Each 2-tablespoon (32-gram) serving of peanut butter contains (2):

  • Calories: 191
  • Total fat: 16 grams
  • Saturated fat: 3 grams
  • Monounsaturated fat: 8 grams
  • Polyunsaturated fat: 4 grams

However, not all high-fat or high-calorie foods are unhealthy. In fact, peanut butter is extremely nutritious.

For one, 75% of its fat is unsaturated. Research shows that eating unsaturated fat instead of saturated fat may help reduce levels of LDL (bad) cholesterol and lower your risk of heart disease (3, 4).

Peanut butter is also packed with protein, fiber, and many essential vitamins and minerals, including manganese, magnesium, phosphorus, vitamin E, and B vitamins (2).


Peanut butter is high in calories but loaded with healthy fats, fiber, and essential vitamins and minerals.

Weight gain occurs when you take in more calories than you burn.

Thus, peanut butter is unlikely to lead to weight gain if eaten in moderation — in other words, if you consume it as part of your daily calorie needs.

In fact, most research links intake of peanut butter, peanuts, and other nuts to lower body weight (5, 6, 7, 8).

One observational study in over 370,000 adults found that regularly eating nuts was associated with less weight gain. Participants also had a 5% lower risk of gaining excess weight or becoming obese during a 5-year period (9).

That said, people who eat nuts have healthier lifestyles in general. For example, people who ate nuts in this study also reported more exercise and tended to eat more fruits and vegetables than those who didn’t eat nuts (9).

Nonetheless, this study suggests that you can include peanut butter in a healthy diet without risking unwanted weight gain.

On the other hand, if weight gain is your goal, you must eat more calories than you burn, preferably from nutrient-dense foods. Peanut butter is an excellent option because it’s packed with nutrients, inexpensive, and easy to add to your diet.


Peanut butter is unlikely to lead to unwanted weight gain if eaten within your daily calorie needs. Yet, it’s also a nutritious option if you’re seeking healthy weight gain.

Peanut butter may benefit your weight loss plan by promoting fullness, preserving muscle mass, and maintaining weight loss long-term.

May help keep you fuller for longer

Peanut butter is very filling.

In a study in 15 women with obesity, adding 3 tablespoons (48 grams) of this spread to a high-carb breakfast lowered appetites more than a high-carb breakfast alone (10).

What’s more, those who ate peanut butter had more stable blood sugar levels, which may play a role in lowering appetite (10).

This nut butter also contains high amounts of protein and fiber — two nutrients known to promote fullness (11).

Interestingly, studies note that whole peanuts and other nuts may be at least as filling as peanut butter (12, 13, 14).

Thus, eating a variety of nuts and nut butters may provide the greatest benefits.

Protein helps preserve muscle mass

Muscle loss and weight loss often go hand in hand.

However, research shows that eating adequate protein from foods like peanut butter may help you preserve muscle mass while dieting (15, 16, 17).

In one study, men with excess weight followed either a high-protein or normal-protein weight loss plan. Though both groups lost similar amounts of weight, those following the high-protein plan lost about one-third less muscle (16).

Not only is preserving muscle important for maintaining your strength, but it also helps sustain your metabolism. In general, the more muscle you have, the more calories you burn throughout the day, even while resting (18).

May help you stick to your weight loss plan

The most successful weight loss plans are ones that you can maintain long term.

Being flexible with your diet is likely a good approach. According to research, weight loss plans that are individualized to include foods you enjoy may be easier to follow over time (19).

Interestingly, studies also show that dieters may better comply with weight loss plans that allow nuts, including peanut butter (20).

Overall, peanut butter may be worth adding to your diet in moderation — especially if it’s one of your favorite foods.


Weight loss plans that include your favorite foods, such as peanut butter, may be easier to follow over the long term.

Peanut butter goes well with just about anything.

You can spread it on toast for a simple snack or use it as a dip for apple slices and celery sticks.

When grocery shopping, aim for products with no added sugar and minimal additives. A simple ingredient list of only peanuts and salt is best.

You can also add this spread to fruit smoothies, oatmeal, muffins, and other dishes for a tasty boost of healthy fats and protein.

To avoid exceeding your daily calorie needs, be mindful of portion sizes. For most people, this means sticking to 1–2 tablespoons (16–32 grams) per day. Visually, 1 tablespoon (16 grams) is about the size of your thumb, while 2 (32 grams) is about the size of a golf ball.


Opt for peanut butter that contains no added sugar and has a simple ingredient list, such as peanuts and salt.

Many dieters avoid peanut butter because it’s high in fat and calories.

Yet, moderate intake is unlikely to lead to weight gain.

In fact, this spread is highly nutritious and may support weight loss by promoting fullness and preserving muscle mass while dieting.

Plus, flexible diets that include tasty foods, such as peanut butter, may be easier to follow over the long term.