How much protein should you eat each day as you age? Here's what to know

Aging is associated with several problems, and high on the list is progressive loss of muscle mass. On average, we start losing muscle after it peaks at age 30-35, but the process speeds up after age 50 and goes into overdrive at age 70. Ultimately, unless you take significant steps to avoid it, the typical American has only about half the muscle mass at age 80 when compared to the peak.

The loss of muscle mass is not obvious, however, as bodyweight tends to either stay the same or increase, hiding the loss of muscle. Sedentary living and inadequate dietary protein intake combine to cause muscle loss. In turn, lost muscle mass reduces the body’s metabolism , and you burn fewer calories (kcals) throughout the day, leading to increased body fat.

In other words, as muscle is lost, it is replaced by body fat.

To offset at least some of this loss, I have been preaching about the benefits of resistance training , and how it becomes increasingly more important the older you get. But even in those who train vigorously well into their advanced years, there will still be some muscle loss. This has inspired considerable research into the variety of factors that may contribute to muscle loss with age, and a big one is anabolic resistance , the reduced ability to take dietary protein and synthesize it into muscle protein. This process is critical to the effective functioning of the body because old cells are constantly wearing out and needing to be replaced. When old muscle cells die off faster than they can be replaced, as occurs with aging, the body deteriorates.

All cells of the body do not follow the same script. For example, red blood cells live about 120 days, then die and are automatically replaced. The problem with muscle is that when it is lost, it is not automatically replaced unless there is an incentive to replace the loss. If you are inactive, your body sees muscle as an unnecessary luxury and it will get rid of it. Being confined to a hospital bed is an extreme of inactivity, and it’s easy to lose several pounds of muscle in a relatively short period. In contrast, if you regularly challenge your muscles with resistance training, you convey the message to your body that your muscles are important and highly valued, and you want to keep them around.

Resistance exercise that challenges the muscles alerts muscle cells, “waking them up” and making them more sensitive and welcoming to dietary protein. Two or three resistance training workouts per week is recommended. Let me emphasize the importance of truly challenging your muscles, pushing them to fatigue and failure on each set. In other words, merely going through the motions isn’t going to accomplish much.

So, push your muscles and consume a generous dose of dietary plant protein.

How much protein should you eat each day?

In order to maximize the effects of resistance training, you need high-quality dietary protein to promote increased muscle protein synthesis. This is a challenge because a major problem with aging is the loss of appetite and consuming fewer calories. This results in a number of problems associated with malnutrition, and a huge one is lack of adequate protein intake.

It used to be thought that the very young need large amounts of protein because the body is in a dynamic state of growth and development. But with maturity, it was thought that protein intake should decrease, and when you are in your baby boomer years and beyond your protein needs are much less.

New research says this is wrong.

Recent research findings on this topic suggest the elderly need more protein, not less, and as much as 30% more than the recommended daily allowance of 0.36 grams of protein per pound. So for a 150-pound person, the RDA would be 54 grams of protein per day (150 x .36= 54). Adding 30% to that would boost it to 70 grams.

What type of protein should I eat as I age?

So, add more protein to your diet, but don’t stop there. The most recent research findings from the ongoing Nurses’ Health Study published in the American Journal of Clinical Nutrition indicate that the source of additional protein is important. The key is replacing calories (kcals) from carbohydrates, fat, and “animal” protein with plant protein. This provides the greatest benefit, including less risk of frailty in old age, plus better mental function. In contrast, although the emphasis is on increased protein intake, if that protein comes from animal sources it can backfire, contributing to premature death, likely from heart disease.

An easy source of plant protein is soy high-protein powder you can add to a blend with fruits and vegetables, and when snacking, grab some nuts and skip the sweets and chips. In addition, rethink your meals by adding beans, peas, whole grains, lentils, etc. This change will not only provide a rich source of soluble and insoluble fiber, it also will add antioxidants to fight free radicals, plus anti-inflammatory phytochemicals (plant chemicals).

In addition to bolstering protein intake overall, another important factor is when you consume it. It’s best to space your protein intake evenly across the day at all three meals and possibly a snack later in the day. You will be more efficient at digesting and using protein if you take it in smaller and more consistent amounts.

Reach Bryant Stamford, a professor of kinesiology and integrative physiology at Hanover College, at stamford@hanover.edu .

This article originally appeared on Louisville Courier Journal: How much protein should you eat each day as you age? Here's what to know