Dietitian Daria Rusakova warned that completely replacing animal protein with plant-based foods can lead to weight gain and nutrient deficiencies, according to Russian outlet Tsargrad.
Rusakova said adults can meet their daily protein targets through plant foods, but doing so comes with several nutritional drawbacks. She noted that an adult man needs roughly 75 to 120 grams of protein a day, while an adult woman requires about 60 to 90 grams.
Legumes offer substantial amounts of protein by weight. Soy contains up to 35 grams of protein per 100 grams of food, while lentils and beans each provide about 20 grams per 100 grams, and peas contain slightly less.
Amino acids and digestion issues
Despite those figures, Rusakova explained that plant protein is incomplete in essential amino acids. Essential amino acids are compounds the human body needs to build tissue that must come from food because the body cannot produce them on its own.
To match the protein value of meat using only plants, a person has to eat more carbohydrates, which Rusakova said inevitably leads to weight gain. Plant protein is also harder for the body to absorb because of its fiber content.
Legumes also contain antinutrients, which are natural plant compounds that reduce the body's ability to absorb nutrients. Because of them, Rusakova said legumes must be soaked, sprouted, and cooked thoroughly for a long time.
Vitamin deficiencies and at-risk groups
Cutting out animal protein also threatens a vitamin B12 deficiency, which harms the nervous system and blood formation, Rusakova noted. Avoiding animal protein can also cause shortages of zinc, vitamin D, and Omega-3.
The Tsargrad report advised against giving up meat, poultry, and fish entirely, recommending that people include them in their diet at least two to three times a week. Reducing animal protein is strictly contraindicated for pregnant and breastfeeding women, and it remains essential for children and teenagers.
In older adults, a protein shortage speeds up muscle loss and leads to sarcopenia, an age-related condition marked by declining muscle mass and strength. Earlier, dietitians Alyssa Pacheco and Drew Rosales named the main healthy and affordable food of the popular Mediterranean diet.
