Peanuts are more than just a popular snack—they’re packed with nutrition and offer impressive health benefits. Though often mistaken for tree nuts, peanuts are actually legumes, related to beans and lentils. Commonly consumed roasted or as peanut butter in the U.S., peanuts also show up in oils, flours, sauces, and baked goods.
From heart health to weight management, here’s everything you need to know about peanuts.
Quick Takeaway
Peanuts are rich in protein, healthy fats, fiber, vitamins, and antioxidants. They support heart health, may aid weight loss, and help you feel full longer. However, they can cause severe allergies in some people and may contain antinutrients or aflatoxins if improperly stored.
Nutrition Facts (Per 100g of Raw Peanuts)
- Calories: 567
- Protein: 25.8 g
- Carbohydrates: 16.1 g
- Sugar: 4.7 g
- Fiber: 8.5 g
- Fat: 49.2 g
- Saturated: 6.28 g
- Monounsaturated: 24.43 g
- Polyunsaturated: 15.56 g
- Omega-3: 0 g
- Omega-6: 15.56 g
Macronutrients
Fat
Peanuts are high in fat—nearly 50% of their weight. Most of this is healthy unsaturated fat, especially oleic and linoleic acids, which are beneficial for heart health.
Protein
With 22–30% of total calories coming from protein, peanuts are an excellent plant-based protein source. The main proteins, arachin and conarachin, are nutritious but can cause severe allergic reactions in sensitive individuals.
Carbohydrates
Low in carbs (13–16%), peanuts are suitable for people managing blood sugar levels. Their low glycemic index (GI) makes them a smart choice for those with diabetes.
Key Vitamins & Minerals
Peanuts are a great source of:
- Biotin (Vitamin B7) – essential for pregnancy and enzyme function
- Copper – supports heart and immune health
- Niacin (Vitamin B3) – linked to heart health
- Folate (Vitamin B9) – critical during pregnancy
- Vitamin E – powerful antioxidant
- Thiamine (Vitamin B1) – important for energy production and nerve function
- Phosphorus – helps maintain and repair tissues
- Magnesium – supports heart, muscle, and nerve health
Plant Compounds & Antioxidants
Peanuts are loaded with health-promoting compounds:
- p-Coumaric Acid – a strong antioxidant
- Resveratrol – linked to reduced cancer and heart disease risk
- Isoflavones – plant polyphenols with protective effects
- Phytic Acid – may hinder iron and zinc absorption
- Phytosterols – lower cholesterol absorption in the gut
Note: Most antioxidants are concentrated in the peanut skin.
Weight Loss & Appetite Control
Despite being calorie-dense, peanuts don’t typically cause weight gain. In fact, they may help you lose weight due to:
- High protein and fiber content, which increases fullness
- Reduced overall calorie intake when peanuts replace other snacks
- Incomplete digestion of whole peanuts, leading to fewer absorbed calories
- Thermogenic effect of monounsaturated fats and proteins
Other Health Benefits
Heart Health
Peanuts contain heart-friendly nutrients like magnesium, niacin, copper, oleic acid, and resveratrol. Numerous studies suggest regular consumption may lower the risk of heart disease.
Gallstone Prevention
Research shows that regular peanut intake may reduce the risk of gallstones, especially cholesterol-based ones.
Potential Downsides
Aflatoxin Contamination
Improperly stored peanuts can harbor aflatoxins, toxic compounds from mold that may cause liver damage or cancer. Drying and proper storage help minimize this risk.
Antinutrients
Peanuts contain phytic acid, which can slightly impair iron and zinc absorption—mostly a concern in diets lacking diversity or in populations relying heavily on legumes and grains.
Peanut Allergies
Peanut allergies affect ~1% of Americans and can be life-threatening. Individuals with this allergy must strictly avoid all peanut products.
Bottom Line
Peanuts are nutrient-dense, affordable, and widely available. They provide key health benefits including improved heart health, appetite regulation, and potential support for weight loss.
However, they should be eaten in moderation due to their high calorie content—and avoided entirely by those with allergies.
Whether eaten plain, as peanut butter, or in sauces and snacks, peanuts are a powerful addition to a balanced diet when consumed responsibly.