Ask the Nutritionist: Getting Enough Protein | Vegetarian Times Skip to main content

Ask the Nutritionist: Getting Enough Protein

Vegetarian TimesQ: As a fairly new vegetarian, I’m not sure I’m getting enough protein. Is there a formula to figure out how much I need, and is age ever a factor?


A: Protein is the major component of all of your body’s cells, and you’re right, it’s important to make sure you’re getting enough. Recent research indicates that we may need more than previously thought. The recommended dietary allowance (RDA) for all adults is 0.37 grams of protein per pound of body weight, or about 15 percent of your daily calories.

But you probably need more if you exercise, if you’re dieting and as you age. One dramatic study of 855 people found that those who ate just the RDA of protein had alarming bone losses compared to those who ate more than the RDA. Those who ate the least protein lost the most bone mass—4 percent in four years. People who ate the most protein (about 20 percent

of calories) had the smallest losses—less than 1.5 percent in four years, reported the Journal of Bone and Mineral Research in 2000. Although the study was done on older men and women, the results may be important for all adults. “When you’re young, you need protein to build bone.

After age 30, you need it to keep bone from being lost,” says Kathleen Tucker, associate professor of Nutritional Epidemiology at Tufts University. “Keeping bones strong is a life-long effort.”

Dieters, take note: New research has found that a protein-dense diet may be essential for weight loss. It helps maximize fat loss while minimizing muscle loss. That’s important because “losing muscle slows your resting metabolic rate—the speed at which your body burns calories. That makes it harder to maintain a healthy weight and lose fat,” says William Evans, director of the Nutrition, Metabolism, and Exercise Laboratory at the Donald W. Reynolds Center on Aging at the University of Arkansas for Medical Sciences.

Many of us don’t get the RDA for protein. Roughly 25 percent of adults over age 20, and 40 percent of those age 70 and up, fall below it, according to United States Department of Agriculture (USDA) statistics, let alone eat enough to protect bones or muscle. And thin women, dieting women and elderly women—who are especially vulnerable to the ravages of bone and muscle loss—are notoriously low on protein. “Losing muscle causes older people to become weak and frail,” says Evans.

“It seems pretty clear that older adults may need more protein,” agrees dietitian Reed Mangels, nutrition advisor to the Vegetarian Resource Group and co-author of The Dietitian’s Guide to Vegetarian Diets. “Older vegetarians need to concentrate on eating protein-dense foods, such as legumes and soy.” 

Based on the new findings, I now recommend that moderately active people and older adults increase their protein to about 20 percent of their calories, or 0.45–0.54 grams per pound of ideal body weight.

For what this means in real food, see below. If you’re an athlete or body builder, you may need even more. On an individual basis, you can use the following formula to figure out your protein needs.


What you need


You can figure out your own recommended dietary allowance (RDA) for protein. Just grab a calculator, and multiply your ideal weight by 0.37 grams of protein. So if your ideal weight is 150 pounds:


150 lb. x 0.37 grams protein = 56 grams of protein per day


But for active people and older adults, calculate 0.45–0.54 grams of protein per pound of body weight. So, if you’re moderately active and your ideal weight is about 150:


150 lb. x 0.45 grams protein = 68 grams of protein

150 lb. x 0.54 grams protein = 81 grams of protein

This means you should get 68–81 grams of protein per day.


So, what does this mean in terms of real food? Because little protein comes from vegetables, you’ll need to be aware of other foods from which you can obtain the protein you need. By eating regularly from the foods on the list below, you’ll get more than enough. Remember, too, that combining several foods in one recipe makes it easier.


8 oz. milk/yogurt = 8 grams protein

1 cup tempeh = 31 grams

1/2 cup cooked or 1 cup raw vegetables = 2 grams

1 cup cooked beans = 16 grams

1/2 cup tofu = 8 grams

1 large egg = 7 grams

2 Tbs. peanut butter = 8 grams

1 cup low-fat ricotta/cottage cheese = 28 grams

1 oz. nuts = 6 grams

1 cup regular trail mix = 21 grams


Comments on this Article

I don't think Romaine lettuce is a good example. According to that link you get 0.5 grams of protein per cup (250 gms) which is only 2 grams per kilo of lettuce. So for me to get my daily requirement would require I eat twice my body weight in lettuce per day!!

this article is full of outdated information.

For adults with high cholesterol, what is a better combination without the dairy?

What/who to believe? Certainly not the USDA. I just read in some vegan literature that we get too much protein and it's this surplus of protein that is leaching the calcium from our bones. People need to filter the truth from all the garbage the special interest groups are trying to feed us. Vegetables and fruits provide plenty of protein and you don't need any dairy. That's what I believe -- I'm sure the US Dairy Council would disagree. Milk doesn't do a body good -- that's just an advertising campaign. And it's a myth we don't get enough protein. Only people who are actually starving don't get enough protein.

to Karen: It's an excess of _animal_ protein that leaches calcium from your bones - I think the reason is that animal protein is much more acid than plant-based. (Ref. The McDougall Program for a Healthy Heart, Dr. John McDougall) Beans contain a lot of protein as long as it's "complemented" sometime during the same day with grains to fill out the amino acid profile, yes. Fruit, not so! What was the vegan literature?

Please speak to menopause. I seem to be needing so much more protein now. Soy protein in excess (and it doesn't take much frankly) is wreaking havoc with my natural hormones.

"because so little protein comes from vegetables..." NOT true. If you are eating your calories from a whole food vegan diet in good variety you will easily get enough protein. Get the calculator out, look up the nutritional value of some vegetables, throw in a few beans, nuts now and then and see. For example, check out the nutritional value of romaine lettuce, here, . At 0.58 g of protein per 8 calories, 2000 calories in a day, if you ate your weight in just this lettuce alone you would get 145 g of protein.

150 lb = 68038.855 g.. Yes I can certainly see someone eating that much lettuce. Just to get to 40 g of protein you'd need to eat over 3,000 g of the lettuce or almost 7 pounds of the stuff!