Peanut Butter
Food · Fat & Oil · Food, Typed Supps
Peanut butter is packed with plant fat and protein that keep you full for hours — it's not empty calories.
Stage by stage
- Chewing & Release (Mouth): Chewing breaks down peanut butter's dense matrix of fat, protein, and fiber, mixing it with saliva to begin digestion.
- Gastric Breakdown (Stomach): In the stomach, the high fat content slows gastric emptying while pepsin starts breaking down peanut proteins, which extends the feeling of fullness.
- Absorption (Small intestine): In the small intestine, bile emulsifies the monounsaturated fats and bound vitamin E for absorption, while niacin, magnesium, and biotin cross the intestinal wall alongside digested amino acids.
- Circulation & Use (Bloodstream & tissues): Absorbed fatty acids fuel cells or are stored as energy, niacin becomes NAD+/NADP+ enzyme cofactors, vitamin E protects cell membranes, and magnesium supports nerve and muscle function throughout the body.
Timing
Peanut butter's own fat content makes it a naturally good vehicle for its fat-soluble vitamin E, and it's commonly paired with carbohydrate-rich foods like bread or fruit, where its protein and fat help slow the resulting rise in blood sugar.
Time to effect
- Weeks: The full feeling from peanut butter's fat, protein, and fiber sets in within one to two hours, but measurable cholesterol improvements from swapping saturated fat for peanut butter's monounsaturated fat typically take several weeks of regular consumption to show up in blood tests.
Allergens
Contains: Peanuts. May contain: Milk, Soya. Derived from what this food is, not from a product label.
Eating patterns
Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher, Low-FODMAP, Gluten-free.
Satiety
70 on the satiety index, where white bread is 100 — low. Modelled from the Holt et al. (1995) measurements.
Environmental footprint
2.9 kg CO2e and 1852 litres of freshwater per kg, matched to "Groundnuts" in Poore & Nemecek (2018), Science 360.
Cost band
Mid — roughly £8 per kg, as a band midpoint rather than a price.
Key nutrients
Nutrition per 100g
- Calories: 596.3
- Protein: 22.2g
- Carbohydrate: 14.3g
- of which sugars: 8.6g
- Fat: 49.6g
- of which saturated: 8.8g
- Fibre: 5.8g
- Sodium: 477mg
Food vs. supplement
Two tablespoons of peanut butter provide niacin, vitamin E, magnesium, and biotin bundled with about 7-8g of protein, roughly 2g of fiber, and predominantly monounsaturated fat — a combination isolated supplements can't replicate.
Kitchen tip
Store peanut butter with any separated natural oil stirred back in, refrigerate after opening to slow rancidity, and choose varieties without added sugar or partially hydrogenated oils.
Common myth
"Peanut butter is just greasy junk food with empty calories." In reality: About half its fat is monounsaturated, mainly oleic acid, and a 2-tablespoon serving supplies roughly 7-8g of protein, about 2g of fiber, and notable amounts of niacin, vitamin E, magnesium, and biotin — a nutrient profile closer to whole nuts than to processed snack fat. It also carries genuine cautions: peanut allergy is one of the most common and severe food allergies, and peanut butter's arginine content can trigger cold-sore outbreaks in people prone to herpes simplex flare-ups.
Recipes that use it
More in Fat & Oil
In the glossary
Sources