Protein is an essential nutrient meaning we have to get it through our diet. One of its primary functions is building and preserving muscle mass. Protein is critical for both young and old to support growth as we develop and to counteract the decrease in absorption and metabolism as we age. With athletic performance and popularity in diets such as keto, there are misconceptions on just how much protein we need and whether some of the products in the marketplace are worth using. This week Dr. Sears answers some of the top questions we receive about protein.
Q: The Zone Diet has long been thought to be a high protein eating plan, can you put this myth to bed?
A: The Zone diet is a protein adequate nutritional plan. The amount of protein one requires is individualized as it depends on the existing muscle mass and level of physical activity. Furthermore, once the total of amount of protein is determined, it is spread evenly throughout the day to be balanced with moderate amounts of low-glycemic carbohydrates. This helps to stabilize blood glucose levels while simultaneously increasing satiety through the release of gut hormones that instruct the brain to stop eating.
Q: How much protein do you recommend people consume each day? Does this amount vary from what you’ve previously recommended with your Zone Food Blocks?
A: It depends on the amount of protein required to maintain your muscle mass. Usually that is 90 grams of protein for females and about 110 grams for males. However, the amount at any one meal is on average about 25 grams. The Zone Food Blocks take into account that the protein density in a protein source is variable with meat being more dense in protein than fish. For example, 1 ounce of meat is 1 block of Zone Protein whereas 1.5 ounces of fish is 1 block of Zone Protein. Both equal approximately 7 grams of protein.
Q: Numerous studies have shown the connection between consuming red and processed meats and the increased risk of heart disease and certain cancers. A recent study published in Annals of Internal Medicine suggests this may not be true and that data regarding the health benefits of consuming less meat is weak. What are your thoughts on this controversial study?
A: There is a large body of research that suggests that red meat consumption, especially processed meats, is associated with the increased risk of cardiovascular disease, diabetes, certain cancers and early death. The data here is clear.
So what protein sources should you use? Relative to red meat, if you are to consume it, aim for grass-fed beef instead. Better choices for animal protein are low-fat chicken or fish. For lacto-ovo vegetarians, egg whites and dairy products are excellent protein choices. Finally, for vegans, plant-based imitation meat products are a useful choice. With these options just be careful to watch the number of ingredients. Typically the more ingredients you see on the label the less desirable the product is going to be.
Q: Is there a difference between the protein you get in vegetables compared to meat?
A: Vegetable protein has a far lower protein density. This requires you to consume a lot of vegetables to get the average 25 grams of protein per meal as recommended on the Zone diet. However, some vegetables such as mushrooms and the ABCs (artichoke, asparagus, broccoli, cauliflower, and spinach) have higher protein contents than other vegetables. Vegetable protein is usually lower in essential amino acids than animal, egg, or dairy protein. However, if you consume 25 grams of vegetable-based protein at a meal, you will have adequate levels of all amino acids. New sources of plant-based meat imitation products make it easier to consume the necessary protein needed for hormonal balance and satiety.
Q: Many people are trying the keto diet right now for its touted weight loss and health benefits. The keto diet is a high fat, high protein eating plan. Do you think the benefits of keto are supported in the literature?
A: The short answer is no. I published a highly controlled study in the American Journal of Clinical Nutrition in 2006 demonstrating the Zone diet was superior in all aspects compared to a ketogenic diet. Furthermore, follow-up studies indicated the ketogenic diet caused fatigue upon mild exercise and calcium loss. Since a ketogenic diet is deficient in glucose, there is also a corresponding increase in cortisol secretion with its continued use. Finally, a ketogenic diet is deficient in fermentable fiber and polyphenols that are essential for gut health.
Q: Collagen levels decline with age. Supplementation has been promoted to help boost levels as we age while helping to improve muscle mass, joint health, and skin elasticity. What are your thoughts on collagen and do you think its supplementation can help with anti-aging?
A: The short answer again is no. All the consequences of aging are due to increased unresolved inflammation. Collagen supplementation is fine for fingernails, hair, and structural components of the skin, but it is a very poor-quality protein and will have no effect on reducing inflammation. Since absorption and metabolism of protein declines with age its also critical to ensure that you are getting enough high quality protein in your diet to help preserve muscle mass and minimize frailty.