A research study comparing the impact of plant meat versus animal meat intake on cardiovascular risk factors was published in August 2020.
The randomized crossover trial of 36 generally healthy meat-eating adults (mostly female, caucasian, and college-educated) was conducted in the United States and funded by Beyond Meat.
Participants were instructed to consume at least 2 servings of plant or animal meat per day for 8 weeks, keeping all other food and drink the same. Half of the participants ate plant meat for 8 weeks and then switched to animal meat for 8 weeks, while the other half ate animal meat first and then switched to plant meat.
Tofu, tempeh, and fish were excluded during the plant meat phase. Animal meat came from grass-fed cows, pigs, and chickens (fish was minimized). Calorie, protein, fiber, and sodium intakes were similar between phases. During the plant phase saturated fat intake was significantly lower (p<0.01).
LDL cholesterol (p=0.002) and weight (p<0.001) were significantly lower after the plant meat phase compared to the animal meat phase. There were no significant differences in IGF-1, insulin, glucose, HDL cholesterol, triglycerides, blood pressure, or in the microbiome.
There is emerging evidence that trimethylamine-N-oxide (TMAO) is a risk factor for cardiovascular disease. TMAO is a metabolic byproduct of carnitine and choline, and is associated with animal meat intake. TMAO spiked during the animal phase for those who received animal meat first. Longer studies would be needed to better understand how transitory such a spike might be or if there’s any clinical relevance.
In conclusion, this small, short-term study found that replacing animal meat with plant meat resulted in lower saturated fat intake, and reduced LDL cholesterol and TMAO.
Crimarco A, Springfield S, Petlura C, et al. A randomized crossover trial on the effect of plant-based compared with animal-based meat on trimethylamine-N-oxide and cardiovascular disease risk factors in generally healthy adults: Study With Appetizing Plantfood-Meat Eating Alternative Trial (SWAP-MEAT) [published online ahead of print, 2020 Aug 11]. Am J Clin Nutr. 2020;nqaa203.