Meat substitutes: a small LDL drop in short trials, and a lot depends on the product

A meta-analysis of 7 randomized trials in 369 adults without heart disease found that swapping meat for plant-based meat alternatives for up to 8 weeks came with LDL cholesterol 9.7 mg/dL (0.25 mmol/L) lower (95% CI 0.08 to 0.42) and body weight 1.6 lb (0.72 kg) lower. The trials were short and their results varied a lot (I2 66 percent). A 6 day crossover in 41 adults, a third with atherosclerotic disease, found two 113 g plant-based patties a day lowered LDL by 6.0 mg/dL against red meat and raised weight by 1.3 lb (0.6 kg). That trial was open label. In 52 women of reproductive age with iron deficiency, 4 oz a day of beef or plant-based meat for 8 weeks gave no difference in blood pressure, glucose control or lipids. "Meat substitute" covers very different products, and the trials mostly tested burgers of the Beyond Meat type.

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• One cup of fried cereal and vegetable protein meat substitute (146 g) provides about 524 calories, 18.7 g protein, 412 mg sodium and 6.2 mg iron. — US survey food composition, per 146 g cup of cubes Evidence E source
  Per 100 g: 359 calories, 12.8 g protein, 282 mg sodium, 4.24 mg iron

What a real portion looks like

• In a randomized trial in 115 UK meat eaters, 4 weeks of free meat substitutes with guidance cut meat intake by 63 g a day, and by 39 g a day four weeks later. — Adults eating meat at least 5 times a week, Oxford, UK (n = 115) Evidence B source
  Meat intake -63 g/d at 4 weeks (95% CI 44-82), -39 g/d at 8 weeks (95% CI 16-62)

What your body absorbs

• In an 8-week randomized trial in 89 Singaporean adults, plant-based meat analogs raised folate and B12 status, but their higher calcium and iron intake did not raise blood levels. — Adults replacing habitual protein foods with fixed amounts of PBMA or animal meat for 8 weeks (n = 89) Evidence B source
  Plasma B12 382.56 vs 357.76 pmol/L (P = 0.004), folate 32.13 vs 23.62 nmol/L (P = 0.003)
• In an 8-week randomized trial in 52 iron deficient women taking 32 mg iron daily, iron status improved equally whether lunch contained beef or plant-based meat. — Nonpregnant women of reproductive age with iron deficiency, 4 oz beef or Beyond Meat daily for 8 weeks (n = 52) Evidence B source
  Iron status and anemia indicators improved (P < 0.05), no difference between beef and plant-based meat
• A systematic review of 19 human intervention studies reports that meat analogs gave lower protein bioavailability than meat, without changing muscle protein synthesis. — Adults in 19 intervention studies substituting animal meat with plant-based analogs Evidence C source
  Lower protein bioavailability and smaller plasma essential amino acid rise, no effect on muscle protein synthesis

What it does to your health

• A meta-analysis of 7 RCTs in 369 adults found swapping meat for plant-based meat alternatives for up to 8 weeks lowered LDL cholesterol by 9.7 mg/dL (0.25 mmol/L). — Adults without cardiovascular disease, 7 RCTs, 60% women, age 24-61 (n = 369) Evidence A source
  LDL -9.7 mg/dL (95% CI -16 to -3.1; metric: -0.25 mmol/L, -0.42 to -0.08), total cholesterol -11 mg/dL (95% CI -20 to -2.3; metric: -0.29 mmol/L, -0.52 to -0.06), weight -1.6 lb (-0.72 kg)
• In a 6-day randomized crossover trial in 41 adults, plant-based meat patties instead of red meat lowered TMAO and LDL cholesterol by 6 mg/dL. — Adults aged 18-80, 32% with atherosclerotic disease, two 113 g patties daily for 6 days (n = 41) Evidence B source
  TMAO -0.61 log units (95% CI -0.90 to -0.33), LDL -6.0 mg/dL (95% CI -10.0 to -1.9), weight +1.3 lb (0.6 kg)
• In a randomized crossover trial in 36 middle-aged adults, a plant-based meat alternative caused no different inflammation response over 5 hours than grass-fed or grain-fed beef. — Adults mean age 46.5, BMI 25-35, single test meals (n = 36) Evidence B source
  No difference in CRP, IL-6, TNF-alpha across meals (P = 0.64)
• A systematic review of 5 RCTs with 122 people found eating mycoprotein lowered energy intake at the next meal and insulin, with unclear effects on blood glucose. — Healthy lean, overweight and obese adults, acute studies (n = 122) Evidence A source
  Lower ad libitum energy intake and insulinemia, glycemia effect unclear

Safety, limits and interactions

• In a crossover feeding trial in 17 breastfeeding women, 12 oz a day of plant-based beef substitute doubled lauric acid in breast milk and lowered arachidonic acid versus beef. — Lactating women exclusively breastfeeding, two 6-day diet phases (n = 17) Evidence B source
  Lauric acid 9.32 vs 4.47% (P < 0.001), arachidonic acid 0.35 vs 0.41% (P < 0.001)

What people believe that the data does not support

• A UK survey of 147 plant-based meat imitation products found less saturated fat but more sugar than meat products, at a higher price per 3.5 oz (100 g). — Products in five UK supermarkets (147 plant-based, 1228 meat-based) (n = 1375) Evidence C source
  Lower saturated fat and protein, higher sugar and fiber per 3.5 oz (100 g), median 1.02 vs 0.85 GBP per 3.5 oz (100 g)

Who this works differently for

• In the same 8-week trial in 52 iron deficient women, 4 oz a day of beef or plant-based meat had no different effect on body composition, blood pressure, glucose control or lipids. — Nonpregnant women of reproductive age with low iron stores, 8 weeks (n = 52) Evidence B source
  No between-group differences. Insulin +0.38 uIU/mL and glucose +3.22 mg/dL over time in both groups
• In a randomized trial in 30 men with cirrhosis, a vegan or vegetarian burger with 20 g protein did not raise blood ammonia over 3 hours, while a meat burger did. — Outpatient men with cirrhosis on a Western diet, single 20 g protein burger meal (n = 30) Evidence B source
  Serum ammonia rose from baseline only in the meat group

The bottom line

Composition swings with the product. The one US survey record, a fried cereal and vegetable protein substitute, gives 524 calories, 18.7 g of protein, 412 mg of sodium and 6.2 mg of iron per 146 g cup of cubes, and brands differ widely from that. A count of 147 plant-based products in five UK supermarkets found them lower in saturated fat, higher in sugar and more expensive than meat options, a median 1.02 against 0.85 pounds per 3.5 oz (100 g), going by labels. What the body gets from them is mixed. In 89 Singaporean adults over 8 weeks, fortified meat analogs raised plasma B12 to 382.56 against 357.76 pmol/L and folate to 32.13 against 23.62 nmol/L, while their added calcium and iron did not move blood levels. In the 52 iron deficient women, iron status improved equally with beef or plant-based meat, but everyone also took 32 mg of iron a day, which may have hidden any gap. A narrative review of 19 intervention studies reports lower protein bioavailability than meat, with muscle protein synthesis and physical performance unchanged. A review of 5 short trials in 122 people found mycoprotein lowered energy intake at the next meal and insulin, and its effect on blood glucose is still unclear. A single meal gave 36 middle-aged adults no different inflammation markers from grass-fed or grain-fed beef (P = 0.64). As a tool for eating less meat, free substitutes plus guidance cut intake in 115 UK meat eaters by 63 g a day at 4 weeks and 39 g a day at 8 weeks, by their own food diaries. We found no study on soy, wheat gluten or pea allergy to these products. That is missing evidence, not a clean record. For breastfeeding women, 12 oz a day of a plant-based beef substitute for 6 days roughly doubled lauric acid in breast milk, 9.32 against 4.47 percent, and lowered arachidonic acid to 0.35 against 0.41 percent in 17 women. Nobody measured what that meant for the babies. In 30 men with cirrhosis, blood ammonia rose after a 20 g protein meat burger and not after vegan or vegetarian ones, over a single meal.

Sources

1. msb-daily-r5-01 · Food composition dataset
   Meat substitute, cereal- and vegetable protein-based, fried, fdc_id 2709163: Energy 359 KCAL, Protein 12.8 G, Sodium, Na 282 MG, Iron, Fe 4.24 MG per 100 g; 1 cup, cubes 146 g
   USDA FoodData Central survey (FNDDS) 2024-10-31, fdc_id 2709163 · checked 2026-09-30
2. msb-daily-r5-10 · Randomized controlled trial
   Relative to the control condition, the intervention reduced meat consumption at 4 weeks by 63 g/d (95% CI: 44-82; P < 0.0001; n = 114) and at 8 weeks by 39 g/d (95% CI: 16-62; P = 0.0009; n = 113), adjusting for sex and baseline consumption.
   Am J Clin Nutr, 2022 · checked 2026-09-30
3. msb-daily-r5-04 · Randomized controlled trial
   While the fortification of certain micronutrients like folate and vitamin B12 may improve the nutritional status, calcium and iron supplementation did not translate to observable changes in circulating micronutrient status.
   Clin Nutr, 2026 · checked 2026-09-30
4. msb-daily-r5-05 · Randomized controlled trial
   Indicators of iron status and anemia improved after 8 weeks (P < 0.05 for all) but did not differ between Animal and Plant.
   J Nutr, 2026 · checked 2026-09-30
5. msb-daily-r5-13 · Systematic review
   PBMAs generally resulted in lower protein bioavailability and a smaller increase in plasma essential amino acids in comparison to AM. However, muscle protein synthesis and physical performance were not affected.
   Nutrients, 2024 · checked 2026-09-30
6. msb-daily-r5-02 · Meta-analysis of RCTs
   The substitution of PBMAs for meat was associated with significant reductions in LDL-cholesterol: -0.25 mmol/L (95% CI: -0.42, -0.08 mmol/L; I2 = 65.8%; n = 7), total cholesterol (TC): -0.29 mmol/L (95% CI: -0.52, -0.06 mmol/L; I2 = 64.8.%; n = 6), and body weight: -0.72 kg (95% CI: -1.02, -0.42 kg; I2 = 0%; n = 5).
   Am J Clin Nutr, 2025 · checked 2026-09-30
7. msb-daily-r5-03 · Randomized crossover trial
   Compared with the red-meat supplemented diet, the plant-based meat supplemented diet resulted in lower TMAO levels: -0.61 log units (95% CI -0.90 to -0.33, P < 0.001). The plant-based diet was also associated with lower LDL cholesterol: -6.0 mg/dL (95%CI -10.0 to -1.9), higher body weight: + 0.6 kg (95%CI + 0.1 to + 1.0), and NTproBNP: + 0.19 log units (95%CI + 0.04 to + 0.35).
   Sci Rep, 2026 · checked 2026-09-30
8. msb-daily-r5-07 · Randomized crossover trial
   No significant differences in postprandial inflammatory markers were observed across interventions (P = 0.64).
   Am J Clin Nutr, 2026 · checked 2026-09-30
9. msb-daily-r5-11 · Systematic review
   In conclusion, the acute ingestion of mycoprotein reduces energy intake and insulinaemia, whereas its impact on glycaemia is currently unclear.
   Br J Nutr, 2020 · checked 2026-09-30
10. msb-daily-r5-08 · Randomized crossover trial
    Human milk collected during the substitute diet contained higher levels of tropical oil-derived medium-chain saturated fatty acids, such as lauric acid (12:0: 9.32 ± 1.8 compared with 4.47 ± 1.82, P < 0.001) and lower levels of long-chain polyunsaturated fatty acids (LCPUFAs), including arachidonic acid (20:4n-6: 0.35 ± 0.06 compared with 0.41 ± 0.06, P < 0.001) compared with milk form the beef diet.
    Am J Clin Nutr, 2026 · checked 2026-09-30
11. msb-daily-r5-12 · Cross-sectional study
    Plant-based meat-imitation products available in UK supermarkets were lower in saturated fat, but higher in sugar compared with meat options, and were significantly more expensive.
    Nutr Health, 2026 · checked 2026-09-30
12. msb-daily-r5-06 · Randomized controlled trial
    No between-group differences were observed for body composition, blood pressure, markers of glycemic control, lipids, or lipoproteins.
    J Nutr, 2025 · checked 2026-09-30
13. msb-daily-r5-09 · Randomized controlled trial
    Serum ammonia increased from baseline in the meat group but not the vegetarian or vegan group.
    Clin Transl Gastroenterol, 2024 · checked 2026-09-30