When you’re craving a midnight snack, peanut butter is a tempting choice due to its rich flavor, creamy texture, and sweet and salty taste.

Thanks to its impressive nutrient profile, some health advocates recommend eating peanut butter at night to support muscle growth, stabilize blood sugar levels, and improve sleep quality.

However, it also contains a lot of calories per serving, so you may wonder whether eating this filling food before bed leads to weight gain.

This article explains whether eating peanut butter before bed causes weight gain.

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Peanut butter is a calorie-dense food that’s rich in heart-healthy fats. Just 2 tablespoons (32 grams) provide 204 calories and 16 grams of fat (1, 2).

Therefore, it’s a great food for a healthy, balanced diet, but large amounts may increase your daily calorie intake. If you consume more calories than you burn throughout the day, you may gain weight in the long run (3).

Nonetheless, weight gain is based on many factors, including your age, size, activity level, health status, and overall calorie intake.

In fact, you can eat peanut butter as part of a diet for either weight loss or weight gain depending on what else you’re eating during the day.


Peanut butter is high in heart-healthy fats and calories, meaning that eating too much before bed may lead to weight gain.

Research on the connection between eating late at night and weight gain has turned up mixed results.

Potential for weight gain

A few studies suggest that eating large amounts of food late at night impairs weight loss and raises body weight. However, other factors may also play a role, including your overall diet quality, sleep duration, and other habits, such as skipping breakfast (4, 5, 6).

On the other hand, some research indicates that eating at night may not cause weight gain directly but is linked to dietary habits and lifestyle behaviors that contribute to weight gain, including increased snacking, breakfast skipping, and decreased diet diversity (7, 8, 9).

Benefits for muscle growth and metabolism

Interestingly, several studies have found that enjoying a healthy snack like peanut butter before bed may have health benefits.

According to one review, eating a small, protein-rich nighttime snack may improve overnight muscle protein synthesis, morning metabolism, and feelings of fullness among healthy men (10).

Another small study including active, college-aged men found that consuming a good source of protein before bed increased their metabolism the next morning (11).

Still, specific research on peanut butter is needed.


Results are mixed on the effects of eating late at night. While this habit may be tied to weight gain, studies also show that having a healthy snack at night may increase fullness, muscle growth, and metabolism, particularly for men.

Peanut butter is a good source of many nutrients, including niacin, magnesium, heart-healthy fats, and vitamins B6 and E (1).

Its antioxidants may be associated with decreased heart disease risk (12).

It’s also high in protein, packing over 7 grams into each 2-tablespoon (32-gram) serving (1).

Increasing your intake of protein may reduce food cravings and regulate your appetite. Furthermore, eating enough protein supports muscle growth, wound healing, and healthy growth and development (13, 14).

Peanuts are also a good source of tryptophan, an amino acid that may enhance sleep quality (15, 16).

Plus, your body uses tryptophan to produce compounds like serotonin and melatonin, both of which are also important for regulating sleep (17, 18).

Although there’s no research on the effects of peanut butter on sleep specifically, studies link foods rich in tryptophan to improved sleep quality (19, 20).

Therefore, eating peanut butter or other foods with tryptophan before bed may alleviate sleep issues.


Peanut butter is highly nutritious and rich in protein, which reduces food cravings and promotes muscle growth. It also contains tryptophan, which may enhance sleep quality.

The next time that you’re hankering for a midnight snack, consider your health goals before reaching for the jar of peanut butter.

If you’re trying to lose weight, consider lower calorie snacks like hummus, yogurt, hard-boiled eggs, or fresh fruit instead.

However, if you’re trying to gain weight, build muscle, boost metabolism, or improve sleep quality, snacking on a spoonful of peanut butter can be a good choice, as it supplies key nutrients like protein, vitamins, minerals, heart-healthy fats, and tryptophan.

Just one thing

Try this today: For a nutritious, high calorie snack that you can enjoy before bed or at any time of the day, top a piece of whole wheat toast with peanut butter and sliced bananas. Alternatively, try whipping up some peanut butter energy bites using ingredients like chia seeds, honey, oats, and protein powder.

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