How Much Protein Do We Need?

There is quite a bit of controversy over how much protein we need, particularly as we age. Numbers vary widely from about 20-30 grams a day to at least 30 grams at each meal! With so much conflicting guidance, people are often left wondering how much protein we really need.

• Dr. Valter Longo, a longevity specialist and author of the Longevity Diet, says the average male needs only about 20-30 grams per day. Dr. Steven Grundy agrees and argues that it is pretty well settled science but not everyone agrees.

• Other medical professionals argue that protein should account for between 10-35% of our calories, so between 200-700 calories protein if you consume 2000 calories.

• The Recommended Dietary Allowance for protein is 0.8 grams of protein per kilogram body weight, so if you are a 125-pound woman, you would be consuming about 45 grams of protein.

• On the other end of the spectrum is Dr. Gabrielle Lyon who argues that we should be eating between 1.2 to 1.6 grams per kg of body weight, or approximately 30 grams at each meal for a total of 90 grams, well above the RDA amount!

Unfortunately, I can’t resolve this issue but read further to hear a discussion of Dr. Longo’s and Dr. Grundy’s stances on the protein issue.

• Dr. Grundy explains that almost daily or every other day we replace the entire group of cells lining our gut wall. Hence, we recycle the protein that we shed from our gut wall and have a continuous source of protein within us.

A striking study in 2009 by the American Dieticians Association argued that our protein needs increase as we age, particularly after age 65. Dr. Longo agrees with that we need more protein as we age, but Dr Grundy disagrees, suggesting that the study proved that muscle synthesis peaked at 30 grams in young and old.

• Dr. Grundy argues that if you eat 90 grams of protein instead of 30, the extra 60 grams of protein would be converted into sugar in your liver and then converted into fat. He contends that you can meet all your protein needs for muscle synthesis with 30 grams.

Dr. Grundy believes Americans eat too much protein. He argues that there is no evidence of long living people on a carnivore diet, while there is overwhelming evidence of people living long in blue zones, which have very little animal protein in their diets.

• Dr. Grundy argues that the ketogenic diet of 10% protein, 80% fat will spare your muscles. He notes that while Dr. Atkins’ diet started as a low carb, high fat, moderate protein diet, it morphed into a high protein diet, which contributed to Dr. Atkins himself dying obese.

• He argues that beef eaters have a much higher incidence of breast cancer and that chicken is heathier. He notes that there is a 5GC sugar molecule in beef, lamb, and pork, which promotes inflammation and autoimmunity, attacks our blood vessels, and promotes cancer cell growth.

What happens when your body has too much protein? Dr. Grundy argues that it does not necessarily destroy your kidneys, but he does restrict protein and fruit carbs for his patients with chronic renal failure. He discusses how dangerous fructose is in creating advanced glycation end products (AGEs) and mitochondrial poisons.

• If you are going to eat animal protein, limit beef, lamb, pork to the occasional treat and make sure it is grass fed and grass finished beef. Manufacturers can claim their beef is grass fed even if it was just 1 day of grass fed. You want grass finished, i.e., entirely grass fed.

How do you know if you are getting enough protein? One of last things he as a doctor sees in his patients is too low protein but some elderly patients are unable to synthesize protein in their liver.

• Dr. Longo has shown with his longevity diet that you can do what you want for 25 days a month, but for 5 days straight you should follow a modified vegan fasting diet (600-800 calories). That gives you the equivalent to having followed a caloric restriction diet the entire month. It is like having your cake an eating it too! (More on Dr. Longo’s Fasting Mimicking Diet in a later post.)

So, what kind of protein should you be eating? Dr. Grundy and his wife follow a vegan or vegetarian diet during the week Mon-Fridays, but on weekends, they eat shellfish and wild fish and occasionally beef, maybe once every few months. So where does he get his protein? His protein is primarily coming from plant sources (vegetables, hemp, tofu, flaxseed, lentils and nuts).

**Content provided for educational and informational purposes only. It is derived from information from Dr. Steven Grundy’s podcast. It is not to be considered medical advice.**