How Many Calories in Oyster Mushrooms? Nutrition Facts & Macros

Fresh oyster mushrooms have just 33 calories per 100 g — among the lowest-calorie foods available. A typical serving of 150 g has only 50 kcal. Their meaty texture provides satisfying bulk with minimal calories, making them ideal for volume eating. Cooking in oil adds calories from the fat, but even pan-fried oyster mushrooms remain a low-calorie food.

Yes — oyster mushrooms are excellent for keto with only 3.8 g net carbs per 100 g (6.1 g total - 2.3 g fiber). A generous 200 g serving has just 7.6 g net carbs. Their meaty texture and umami flavor make them one of the best meat substitutes for keto meals. Pan-fry in butter with garlic for a rich, satisfying keto side dish.

Oyster mushrooms contain beta-glucans (pleuran) that support the immune system and may help lower cholesterol. They are one of the few natural sources of vitamin D (0.7 µg per 100 g). High in iron (1.33 mg — unusually high for a mushroom), niacin (5.0 mg), and riboflavin (0.35 mg). Research suggests oyster mushroom extracts have antioxidant, anti-inflammatory, and potentially anti-tumor properties. They also contain lovastatin, a natural cholesterol-lowering compound.

Tear into strips along the natural grain (don't chop — tearing gives better texture). Best methods: pan-fry in butter or oil until golden and crispy edges (4-5 min, don't stir too much), deep-fry in batter for mushroom 'oysters', grill whole clusters with olive oil and herbs, add to soups and stews in the last 5 minutes. Don't overcook — they become rubbery. Don't wash — wipe with a damp cloth. The stems are edible but tougher; trim the very base of the cluster.

Oyster mushrooms are the easiest gourmet mushroom to grow at home. They grow on coffee grounds, straw, cardboard, or hardwood sawdust. Ready-to-grow kits are widely available and produce mushrooms in 7-14 days. They fruit at room temperature (15-25°C) and need indirect light and humidity. A single kit can produce 2-3 flushes over several weeks. Growing your own is economical — fresh oyster mushrooms can cost 15-25 EUR/kg in stores.

Oyster mushrooms have slightly fewer calories (33 vs 34 kcal) and more protein (3.3 vs 2.2 g), more iron (1.33 vs 0.41 mg), and more niacin (5.0 vs 3.9 mg). Shiitake has more zinc (1.0 vs 0.77 mg) and the unique compound lentinan. Flavor-wise, oyster mushrooms are milder and more delicate; shiitake has deeper, earthier umami. Both are excellent for keto. Oyster mushrooms are easier to grow at home and generally cheaper.