Surprising steak news: It's healthy for some of us

For years we’ve been told to focus on plant-based proteins (beans, for example) rather than meats and cheeses from animal-based proteins.

Now all that may change — depending on our age. Two studies, released within a week of each other, concur: In middle age, a high-protein diet makes us four times more likely to die of cancer, especially animal proteins such as cheese, meat and milk, which increases overall deaths. Yet after age 65, an increase in protein is healthy.

One study, reported in the Journal of the American Geriatrics Society, suggests that as we age, we don’t absorb protein like we used to. This lack of protein can lead to a decline in cognitive abilities, as well as how we function in activities of daily living. Researchers studied the diets of more than 1,000 seniors with an average age of 67, looking at their intake of plant versus animal protein, and queried them again seven years later.

Men with the highest animal protein had a 39 percent lower chance of functional decline. Scientists didn’t see similar results in those who had a majority of plant-based protein in their diets.

The other study, in the journal Cell Metabolism, took a closer look at the biology of why protein goes from being bad for us to being good. The growth hormone IGF-I drops off after age 65, and we can become frail with muscle loss without an increase in protein to offset what we’re not processing.

Your best bet: Go to your doctor and ask for a referral to a nutritionist. In the week before you go to your appointment, write down everything you eat to give the nutritionist a baseline of your current food choices. Ask whether, given the two studies, you should make any adjustments in your diet.