How Plant Protein Wins Over Animal Protein

September 28, 2016 by Joel Fuhrman, MD

Health Concerns: Cancer

We are all taught that protein is a super nutrient that will make us lean, strong, and healthy. We do need protein, but more is not necessarily better, and high-protein foods are not always healthful.

Why do we need protein?

In every cell in the human body, the DNA contains a code that tells the cell which proteins to make. Proteins have a lot of different roles in the body, some provide structure like collagen, some facilitate contact or movement, and others act as enzymes, signals, receptors, or transporters. In order to make all of these proteins, we have to consume protein and break it down into its constituent amino acids.

High-protein diets

High-protein foods do tend to be low in glycemic load. This is what the high-protein, low-carb diets get right. They avoid dangerous high-glycemic refined carbohydrates—sugar, white rice, and white flour products. In the process, they also limit dangerous trans fats. It is important to remember though, just like excess carbohydrate and fat calories, if you take in more protein calories than your body can use right away, those calories get stored as fat.

Refined carbohydrates are empty calories that are absorbed quickly, and they lead to overeating. Foods that are higher in protein, fiber, and/or resistant starch provide the satiety factor that is missing in refined carbohydrates and help to prevent blood glucose spikes, so we are not driven to overeat. For some people, high protein diets can be successful for weight loss in the short-term, but because they are so focused on animal foods, they are dangerous in the long-term. Low-carbohydrate/high-protein diets have been linked to increased risk of heart disease, cancer and premature death.1-3

Plant protein vs. animal protein

Although plant protein is often described as “incomplete,” it has been known for many years that all plant foods contain all of the amino acids. Different plant foods may be low in a certain essential amino acid, but as long you are eating a variety of plant foods, you will get adequate amounts—but not too much—of all the essential amino acids.4

Animal protein and plant protein both provide us with adequate amounts of all of the amino acids, but animal protein is more concentrated in complete protein of a high biological value, so the body does not have to wait to utilize it to be combined with amino acids from other foods. Their proteins get absorbed and utilzed quickly, especially the amino acids that raise growth promoting hormones. For these reasons animal protein increases the body’s production of a hormone called IGF-1, which is associated with aging and an increased risk of several different cancers.5-6 One interesting study followed over 85,000 women and 44,000 men for more than 20 years, (26 years in women and 20 years in men) recording over 12,500 deaths. This research team found animal protein-rich diets were associated with a 43% increased risk of death from cardiovascular disease and cancer, compared to diets low in animal protein.7 In addition to animal protein, a diet high in animal products delivers additional harmful, pro-inflammatory, or pro-oxidant substances. Animal foods are higher in arachidonic acid, saturated fat, carnitine and choline, heme iron, substances linked to inflammation, premature aging and other diseases.8-16

How much protein?

The number of grams of protein humans need in a day has been estimated at 0.8 g/kg/day (about 36 grams of protein per 100 pounds of body weight).17 However, it is not important to count the number of grams of protein in the food you eat to make sure you reach this number. If you are eating a variety of foods, it is almost impossible to consume too little protein. For a typical day, a Nutritarian menu of 1700-1800 calories provides approximately 60-70 grams of protein. Green vegetables, seeds, nuts and beans are all relatively rich in protein. The point is that when you eat an anti-cancer diet to promote longevity, you strive to consume more of these low glycemic colorful plants, which contain plenty of protein, to secure adequate amounts even with the increased needs of aging. It is rare that a person needs to eat animal products to get sufficient protein when eating a Nutritarian diet, but even those individuals that require that, can do so with only a small amount, avoiding the dangers of too much animal products. It is these features that lead to the dramatic disease-protective lifespan benefits. Eat Nutritarian, and forget about protein, you will automatically get the right amount; not too much and not too little.

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Joel Fuhrman, M.D. is a board-certified family physician, seven-time New York Times bestselling author and internationally recognized expert on nutrition and natural healing, who specializes in preventing and reversing disease through nutritional methods. Dr. Fuhrman coined the term “Nutritarian” to describe his longevity-promoting, nutrient dense, plant-rich eating style.
For over 30 years, Dr. Fuhrman has shown that it is possible to achieve sustainable weight loss and reverse heart disease, diabetes and many other illnesses using smart nutrition. In his medical practice, and through his books and PBS television specials, he continues to bring this life-saving message to hundreds of thousands of people around the world.