Tempeh vs tofu: carbs, fiber and net carbs

On protein, tempeh and tofu are close. Per 3.5 oz (100 g), tempeh has about 20 g and firm tofu about 17 g, and tempeh carries roughly a third more calories. The bigger gap is calcium. Tofu set with calcium sulfate has about six times the calcium of tempeh, though we found no study of how well people absorb it.

Fermentation does change the soy. In two small crossover trials, people reached higher blood or urine levels of soy isoflavones from tempeh than from unfermented soy. Whether that matters for health is open. A meta-analysis of 15 trials found small drops in waist size and blood sugar with fermented soy, but it pooled tempeh with other fermented soy foods, and a 2026 overview calls the benefits of fermented soy inconclusive.

Soy protein supplements did not add lean mass in young adults lifting weights, and neither did whey. The fear that soy feminizes men was tested in 41 clinical studies, and testosterone and estrogen levels in men did not change.

Neither suits a soy allergy. The EMSAM patch label, at 9 mg/24 h or more, lists most soybean products among foods to avoid. On warfarin, one man's INR dropped after he started soy milk, a single case. Choose calcium-set tofu for calcium and fewer calories, tempeh for a little more protein.

Evidence behind this note

1. Level B At the same isoflavone dose of 0.44 mg per kg body weight, tempeh produced higher peak serum daidzein and genistein and larger areas under the curve than textured vegetable protein in 59 adults, because fermentation leaves the isoflavones mostly as aglycones. J Nutr, 2006
2. Level B Nine days of 112 g tempeh a day gave 17 healthy men significantly higher urinary recovery of daidzein and genistein than 4.4 oz (125 g) of unfermented soybean pieces, even though fermentation had lowered the isoflavone content of the food. J Am Diet Assoc, 1995
3. Level A Fermented soy, the family tempeh belongs to, cut waist circumference by 0.59 in (1.50 cm) and fasting glucose by 6.39 mg/dL across 15 randomized trials. Food Funct, 2025
4. Level C The most recent overview of all the soy meta-analyses calls the evidence more beneficial than harmful, and singles out fermented soy as unresolved. Mol Nutr Food Res, 2026
5. Level A Soy protein at a median 25 g a day for a median 6 weeks lowered LDL cholesterol by 4.76 mg/dL, about 3 to 4 percent. J Nutr, 2019
6. Level A The trials behind the cholesterol claim used a median 25 g of isolated soy protein a day, a study dose rather than a serving of tofu or tempeh. J Nutr, 2019
7. Level A Soy protein supplements did not build lean body mass in 261 young adults doing resistance training across 12 trials. J Diet Suppl, 2026
8. Level A Across 41 clinical studies with testosterone measured in 1,753 men, neither soy foods, soy protein nor isoflavone extracts changed total or free testosterone, estradiol or estrone at any dose or duration, so the claim that soy feminizes men is not supported. Reprod Toxicol, 2021
9. Level E FDA lists soybeans among the nine major food allergens in the United States, together with milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat and sesame. US FDA, Food Allergies
10. Level E The FDA label for transdermal selegiline (EMSAM) at 9 mg/24 h or more puts most soybean products on the avoid list, naming soy sauce and tofu. Tempeh is a soybean product but is not named. EMSAM (selegiline transdermal system), FDA-approved label, sections 2.3 and 7.2 (Table 5)
11. Level D Soy milk dropped one stable warfarin patient below his therapeutic INR, and the value came back within two weeks of stopping it. Ann Pharmacother, 2002
12. Level E United States law still carries a model wording tying 25 grams of soy protein a day to lower heart disease risk. 21 CFR 101.82, Health claims: Soy protein and risk of coronary heart disease (CHD)
13. Level E Europe refused the same cholesterol claim the United States allows: the soy protein and cholesterol wording is non-authorized in the EU register. EU Register on nutrition and health claims, claim POL-HC-6237, snapshot 2026-09-21
14. Level E Since 31 October 2017 FDA has had a proposed rule on the books to revoke the soy protein and coronary heart disease health claim, stating that the totality of evidence no longer supports significant scientific agreement, and as of September 2026 it remains a proposed rule. Federal Register, 2017-23629, Food Labeling: Health Claims; Soy Protein and Coronary Heart Disease (proposed rule)

Written from the studies and agency guidance we hold for both foods, reviewed by the Bioma editorial system. How we verify.

Read more about these foods

• Tempeh and tofu: a small real cholesterol effect, and nobody has compared the two
• Tempeh: the fermentation is measurable, the benefit is pooled
• Tofu: the label America wrote and then took back

What the studies say

• Is tofu good for weight loss? Nobody has tested tofu, and soy moves weight under a kilo

Rankings and guides

• Carbohydrates: what it does and how much you need
• Fiber: what it does and how much you need
• Which foods are highest in dietary fiber?
• Which foods are highest in carbohydrate?
• Added sugar: what it does and what the evidence shows
• Tempeh: full nutrition facts

• Tempeh: USDA FoodData Central, Tempeh, FDC ID 174272 · full profile · all forms of tempeh
• Tofu: USDA FoodData Central, Tofu, raw, firm, prepared with calcium sulfate, FDC ID 172475 · all forms of tofu

Each food is one USDA entry, chosen as it is usually eaten. Other cuts, brands and preparations differ; the links show them. % DV uses FDA Daily Values for adults. How we verify.