In diverse cultures around the world, food variety is both celebrated and encouraged by individuals and health organizations alike. A varied diet helps to meet nutrition needs as well as promote feelings of pleasure and satisfaction.
Meat substitutes are food products engineered to imitate meat, whereas the term “meat replacements” or alternatives often refers to whole foods used as replacements in recipes.
Meat substitutes may be a valuable food source to help people reach their protein needs in the face of declining meat availability and a growing population.
Meat substitutes are lower in branched-chain amino acids, especially leucine, which is required for muscle protein synthesis. Higher intake of plant proteins may result in unfavorable or suboptimal muscle changes.
Specific studies looking at total meat intake have not shown significant health benefits. Fasting research does show however that a 5-day meat restriction paired with fasting exerts some positive health benefits in those that are metabolically unhealthy.
Within a varied diet, one essential component for health that must be consumed is a protein source – whether from plants, animals, or both. Meat substitutes represent a meat-free commercialized attempt at providing food variety in a convenient, protein-rich packaged product.
What are meat substitutes?
Meat substitutes are food products designed to imitate meat using both plant and synthetic ingredients. They are typically created to provide some amount of protein content, as well as contribute to taste, aroma, texture, and other appealing qualities.
The plant-based and meat-substitute options are growing. Popular brands include Beyond Meat, Impossible Foods, ToFurky, Plant Basics, Morning Star, and others.
How are they different from meat replacements?
Though the terms “meat substitutes” and “meat replacements” may be used interchangeably, meat replacements or meat alternatives typically refer to whole foods that provide some level of protein and/or desirable flavor or texture – such as tofu, beans, nuts, lentils eggplant or mushrooms - but are not processed to resemble or imitate meat.
Common meat replacements for recipe swaps, though they may result in inferior protein content, including eggplant, mushrooms, tofu, beans, jackfruit, and cauliflower.
Potential advantages of meat substitutes
According to Don Layman, Ph.D., professor of Food Science and Human Nutrition at the University of Illinois Urbana-Champagne, and a 40-year scientific researcher of dietary protein’s role in muscle protein synthesis, humans may be near capacity for animal-based protein. The development and continued availability of meat substitutes may play a role in helping individuals meet protein needs – more so than carbohydrate sources – when facing meat shortage.
For vegetarians and vegans, meat substitutes offer an opportunity to meet protein and calorie needs in a form that resembles a socially acceptable and common staple food – meat.
Meat substitutes may also work well for those who have milk or shellfish allergies and find it difficult to meet protein needs.
Potential disadvantages of meat substitutes
Some meat substitutes do contain several synthetic ingredients. Professor Don Layman states these companies are relying on the “generally recognized as safe” or GRAS declaration and have not yet proven to the Food and Drug Administration the substances are safe for long-term consumption.
In addition, plant proteins contain lower amounts of essential amino acids required by the body to build and repair muscle tissue. One primary amino acid, leucine, is considered a rate-limiting amino acid. In other words, when the diet is low in leucine, muscle protein synthesis is compromised. This becomes a big concern in those who are at risk of low or decreasing lean body mass such as those over the age of 50, those recovering from surgery or long-term illness, as well as during weight loss. For those desiring to improve body composition and increase muscle mass to improve metabolic and physical health, experts recommend 2-3 grams of leucine per meal. According to Nancy Clark, MS, RD, CSSD, a sports nutrition expert, animal protein has about double the leucine as plant proteins. The difference adds up fast and may make it more difficult to meet high protein needs. This difference may represent one key downside of regularly eating meat substitutes (without ensuring adequate leucine content).
Research on the effects of short-term meat-free eating
While research is plentiful on vegetarian and plant-based diets, results and health outcomes are often paired with confounding factors such as improved health behaviors in those who are vegetarian/vegan/plant-based such as being more physically active, less smoking incidence, more vegetable, and fiber intake, and more.
One meta-analysis of 20 randomized controlled trials of total red meat intake - with an average intervention period of 8 weeks, but up to 16 weeks – found interesting results. No differences were found in major metabolic clinical markers such as glucose, HOMA-IR, insulin, CRP, HbA1c, IL-6, or TNF-α between those who ate less than or more than 0.5 servings (1.25 ounces) of red meat per day.
Research has been performed in the last few decades on the benefits of water fasting and the Fasting Mimicking Diet (FMD), both of which restrict meat intake. Results from a 5-day, 3-cycle, FMD show weight loss, improved metabolic markers, and reduced mTOR activation – a pathway heavily involved in metabolism and aging and often dysregulated in diabetes, obesity, depression, and cancer. Results, however, cannot be distinguished from the effects of a meat-free and/or low-protein diet versus the effects of fasting and caloric restriction. Other FMD studies reveal benefits may be more accentuated in those at risk for metabolic or cardiometabolic diseases such as diabetes, metabolic syndrome, and heart disease.
Tips for choosing the best meat substitutes
With the plethora of options now available in the marketplace, following two simple guidelines below may help you make healthier choices.
- Essential Amino Acid Content - Choose a product with pea, corn, or potato protein as the first listed protein isolate. While still lower than milk, whey, and egg, these specific plant protein isolates are higher in total essential amino acid content (and leucine content) than other plant proteins such as soy, wheat, oat, hemp, and rice.
- Ingredients – aim to consume products that only have a handful of familiar ingredients. Also, avoid those with an extensive ingredient list.
Meat substitutes are becoming more available worldwide. Not only are they offered in grocery stores, but you can also now find them on restaurant and fast-food menus. These meat-substitute food products offer both advantages and disadvantages to the consumer. Understanding meat substitutes, their properties, and their potential effects can help guide you next time you are considering making a meat substitute purchase.
- SpringerLink. Protein content and amino acid composition of commercially available plant-based protein isolates.
- NIH. Effects of Total Red Meat Intake on Glycemic Control and Inflammatory Biomarkers: A Meta-Analysis of Randomized Controlled Trials.
- NIH. Effects of Fasting-Mimicking Diet and Specific Meal Replacement Foods on Blood Glucose Control in Patients with Type 2 Diabetes: A Randomized Controlled Trial.
- NIH. Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease.
- NIH. Fasting in diabetes treatment (FIT) trial: study protocol for a randomised, controlled, assessor-blinded intervention trial on the effects of intermittent use of a fasting-mimicking diet in patients with type 2 diabetes.