High Protein Diets, Friend or Foe?
The relationship between dietary protein intake and bone health is a controversial one. Protein has been reported to be both detrimental and beneficial to bone health, depending on a variety of factors, including the amount of protein in the diet, the protein source, calcium intake and the acid-base balance of the diet.
The amino acids that make up proteins are vital to preserving lean muscle mass and bone health, which makes adequate protein consumption important, especially as we age. However too much protein can be detrimental. Let’s look at how.
Our bodies are constantly trying to maintain a state of alkalinity, which is essential for our immune health and ultimate survival. When we consume excessive amounts of protein, especially animal protein and red meat, our bodies enter a state of metabolic acidosis, during which we deprive our cells of the oxygen needed to function properly. This oxygen deprivation weakens our immune system and makes us vulnerable to all kinds of chronic illness and disease. What’s more, eating a lot of protein creates more acid and toxins in our bodies, and thus the kidneys must work harder to filter out all those substances.
When we are in a state of acidosis, one of the best and most efficient ways to restore body alkalinity is via calcium. What is the most abundant source of calcium in our bodies? Our bones. When there are insufficient levels of dietary calcium available, our bodies will leech calcium from our bones to buffer the acid and bring back the optimal pH balance. If you’re thinking the answer is as simple as upping your calcium intake, you’d only be half right.
For our bodies to properly utilize dietary calcium, we must have enough magnesium available, a mineral most of us are lacking. Many researchers and nutritionists now believe magnesium is more important than calcium to maintain healthy bones.
As with most things in our body, the relationship between calcium and magnesium is symbiotic. Magnesium releases calcium from blood and soft tissues back into the bones, where it is essential to maintain healthy bone structure, while also helping prevent clogged arteries. There are numerous studies pointing to the benefits of magnesium in osteoporosis, osteopathy and heart disease prevention that should not be ignored.
One of the downsides of high-protein diets such as paleo and ketogenic, is the drastic reduction in vegetable and fruit intake. When we drastically reduce the amounts of fruits and vegetables we consume, we are in effect reducing the important phytochemicals and nutrients we need for our bodies to thrive. Focusing solely on protein consumption undeniably leads to imbalances.
A diet low in fruits and vegetables is associated with increased fracture risk; however, nutrient density of the diet seems to have an even stronger correlation. One of the best sources for both calcium and magnesium are leafy greens and microgreens. Kale, spinach, mustard, collard and turnip greens all contain significant amounts of magnesium and calcium. For instance, a 1-cup serving of cooked spinach has 158 mg of magnesium, or 37% of the RDA; 1 cup of cooked collard greens has 268 mg of calcium, or about 21% of the amount that you need in a day. The Villages Grown offers a wide variety of nutrient-dense microgreens and leafy greens.
So how much protein can we safely consume each day? Numerous groups have debated whether the current recommended dietary allowance (RDA) for protein is sufficient to meet the needs of the entire population.
The RDA for protein is currently 0.36 gram of good-quality protein (e.g., balanced in all nine essential amino acids) per pound of body weight per day for adult men and women. The average American man weighs 195.7 pounds, while the average American woman weighs 168.5 pounds. Most men should consume about 71 grams of protein per day. Women should typically consume about 60 grams of protein per day. Athletes, pregnant women and older adults can safely double this amount. However, we risk adverse effects when protein consumption equals more than 1 gram per pound of body weight daily.
Dietary protein levels above the current RDA in the U.S. and Canada, regardless of the source, may be beneficial in reducing bone loss and hip fracture risk, provided calcium and magnesium intakes are adequate. The National Academy of Medicine also defined an acceptable macronutrient distribution range for protein to be 10% to 35% of total calories per day.
If you’re thinking about increasing your protein intake or following a high-protein diet, consider working with a registered dietitian. Be sure to eat plenty of vegetables and fruits to allow for adequate intake of the essential minerals and nutrients your body needs to handle the increased amount of protein.