Are plant-based meats living up to their perceived health halos?

20 Nov 2024 byAudrey Abella
Are plant-based meats living up to their perceived health halos?

With the advent of plant-based diets (PBDs), plant-based meat analogues (PBMAs) have emerged as alternative protein sources carrying numerous health benefits. However, a study from Singapore appears to reflect otherwise, showing that PBMAs do not confer cardiometabolic health benefits compared with their animal-based counterparts.

“We hypothesized that dietary substitutions of animal-based meats with PBMAs will positively influence cardiometabolic health and lower the risks associated with noncommunicable diseases, such as cardiovascular disease (CVD) and type 2 diabetes,” said the researchers.

“[C]ontrary to our hypothesis, we failed to substantiate any clear benefits for a PBMA diet (PBMD) on cardiometabolic health compared with the corresponding animal-based meat diet (ABMD),” they stressed.

Week 8 saw no significant effect on low-density lipoprotein-cholesterol between the ABMD and PBMD groups (3.47 vs 3.48 mmol/L; p for time=0.21; p [interaction coefficient] for time x treatment=0.69). These levels were also not far from the levels reported at baseline (3.51 and 3.60). [Am J Clin Nutr 2024;119:1405-1416]

In this 8-week trial, researchers compared the impact of consuming an omnivorous ABMD against a PBMD on cardiometabolic health among adults with elevated* diabetes risk in Singapore. Eighty-nine participants were instructed to replace their habitual protein-rich foods with fixed quantities of PBMAs (n=44) or their corresponding animal-based meats (n=45; 2.5 servings/day) provided by the research team for consumption in 3-day cycles.

For the ABMD group, the six frozen foods provided were beef mince, pork mince, chicken breast, burger patty, sausage, and chicken nuggets. The corresponding items for the PBMD group were Impossible Beef, OmniMeat Mince, Chickened Out Chunks, Beyond Burger, Beyond Sausage Original Brat, and Little Peckers.

Participants were encouraged to lessen their intake of other protein-rich foods (≤1 serving/3-day cycle) beyond those provided but were instructed to maintain their consumption of other dietary components.

Other outcomes

Significant time effects were observed for fructosamine and homeostatic model assessment for β-cell function (HOMA-β). From week 0 to 8, both arms saw reductions in fructosamine (from 247.2 to 244.7 μmol/L [ABMD] and from 243.9 to 241.9 μmol/L [PBMD]; p for time=0.035) and increases in HOMA-β (from 76.8 to 79 and from 70.7 to 77; p for time=0.006). However, no between-group differences were observed.

Glycaemic homeostasis was better regulated with ABMD vs PBMD as reflected by interstitial glucose time in range (median, 94.1 percent vs 86.5 percent; p=0.041).

“Among the other CV health-related outcomes … no time and interaction effects were observed in terms of clinic systolic blood pressure (BP), high sensitivity C-reactive protein concentrations, and Framingham 10-year CVD risk following the 8-week intervention,” said the researchers.

Nocturnal BP dipping

Of note, there was a marked increase in nocturnal diastolic BP dip in the ABMD group (mean, +3.2 percent); conversely, this dropped in the PBMD group (mean, –2.6 percent; p for interaction=0.017).

The researchers attributed the difference to the high sodium content in PBMAs. “When higher sodium concentrations are consumed and retained during the day, night-time BP increases, resulting in non-dipping.” Nonetheless, based on current AHA and ACC** guidelines, both ABMD and PBMD groups remained as non-dippers postintervention, they noted.

“Nocturnal BP dipping calculated from a 24-hr ambulatory BP monitor is an independent risk factor for CVD,” the researchers said. Evidence shows that a reduction in nocturnal BP dipping is tied to increased arterial stiffness index and vascular inflammation. [BMC Cardiovasc Disord 2021;21:139] The increase in the ABMD group may thus signify potential CV benefits. [Eur J Prev Cardiol 2022;29:e25-e28]

Bursting the health halo bubble

PBMAs have been under the spotlight of late due to their perceived health halos, as well as other factors such as sustainability concerns and animal welfare. [Nat Food 2022;3:90-91; Nutrients 2021;13:2527]

“The advent of PBMAs designed to mimic the organoleptic attributes of their animal-based counterparts sparked remarkable interest globally. Developed from more sustainable plant-based sources, PBMAs have presented our food landscape with a promising opportunity that seemingly addresses planetary and human health concerns,” the researchers explained.

However, these gains come at the expense of inadvertent effects on the health-promoting ingredients inherently present in PBMAs due to the deconstruction and reconstruction involved in the production process, they stressed.

The study implies that assuming health benefits from PBMA consumption may not be directly inferred to those consuming PBDs, the researchers stressed. “[Our findings] suggest that despite the well-documented health benefits of traditional PBDs, [these] should not be conflated with [PBMAs, as they have distinct nutritional properties] and impact on cardiometabolic disease risk.”

“However, this creates an opportunity and stimulus for the food industry to re-evaluate the production of next-generation PBMAs with improved nutritional attributes and bio-accessibility,” the researchers noted.

“Nutritional quality is a key factor to be considered for next-generation PBMAs … The inclusion of nutrition in the current focus on organoleptic properties and sustainability will be beneficial to both manufacturers and consumers in this Asian population and globally,” they concluded.

 

*Raised blood glucose, defined by a fasting blood glucose concentration ≥5.4 and ≤7 mmol/L, and/or HbA1c ≥5.5 and ≤6.4 percent)

**AHA and ACC: American Heart Association and American College of Cardiology