Are Women Eating Enough Protein?

It's not easy to meet the numbers.

Posted Oct 22, 2019

The other day, when ordering lunch in a restaurant known for its salads, my friend was asked whether she wanted, "some protein with her salad." After hesitating a minute, she said no, and when the server left she turned to me and said, “I probably should have ordered grilled salmon, along with the salad. I know I don’t eat enough protein.”

We talked about how most of the women we knew did not eat that much protein, especially if they were cooking only for themselves. “I’ll have yogurt for breakfast and maybe a yogurt for dinner,” she told me. “So that is maybe 25-30 grams of protein a day.  My doctor told me I should be eating about 40-50 grams a day, but I have to force myself to have an egg or bake a chicken breast. Maybe I should just drink one of those fortified protein shakes. “

She was correct about her inadequate protein consumption. The USDA recommends men and women eat about 0.8 grams of protein for every kilogram of body weight. One pound equals 2.2 kilograms so my friends who weigh about 130 pounds need to eat about 45-46 grams of protein a day. But she wasn’t.  

Health surveys that analyze nutrient intake from self-reported food intake questionnaires have shown that in general we eat more than enough protein to satisfy our nutrient needs. Indeed, with so many people following the now popular keto diet, the problem may be eating more than necessary, since the bulk of the calories come from high-protein foods.

But there are individuals who don’t get enough protein: people who eat alone, have dietary restrictions, engage in frequent fasting for weight-loss, or have medical problems that limit the kind and amount of protein that can be consumed. Age itself is a major cause of inadequate protein intake. In a national health survey of over 11,000 adults divided into categories according to age, about 46% of those who were 71 years and older (almost 4,000 in the sample) did not eat enough protein. 

Chronically inadequate protein intake can lead to muscle weakness and even loss of muscle itself. This is turn may cause difficulty in balance, gait, and bone loss. It isn’t hard to get enough protein in one’s diet, but doing so requires some thought and attention.

But why should it be so hard to eat enough protein? Has a trend toward avoiding red meat and eggs contributed to this? Have the fad diets involving cleanses and frequent fasting decreased daily protein intake?  What about the popularity of vegetarian and vegan diets? Non-animal food sources contain protein, so that should not be a cause of inadequate protein intake, should it? My friend’s salad contained some chickpeas and pumpkin seeds; both foods have been suggested as good sources of this nutrient. But an ounce (28 grams) of chickpeas contains only 3 grams of protein. And chickpea protein lacks methionine, an essential amino acid that the body cannot make itself but is necessary to make new protein. Pumpkin seed protein, with other seeds, are a good source of protein, but pumpkin seeds do not have as much lysine, another essential amino acid as our bodies need. Plus, my friend would have to eat a cup to get 12 grams of protein so clearly the handful of pumpkin seeds sprinkled on her salad were not adding much to her protein intake. 

Often travel, work schedules, early evening meetings, classes or a second job makes it hard to eat enough protein at meals. I had a weight-loss client whose job was to visit regional educational facilities. Lunch was anything she could eat in the car during stops at red lights, and peanut butter sandwiches were most reliable for not making a mess of her steering wheel. Her husband traveled for business so she often ate dinner, cereal, and milk, alone. Peanut butter, which she assumed was high in protein, isn’t. Two tablespoons (calories 250) have 8 grams of protein. And her recent switch to oat milk (because she wanted to stop eating dairy products) meant she was getting only 3 grams of protein in her cereal assuming she added eight ounces. Breakfast was either only coffee or buying an egg-white wrap (8 grams of protein) or an egg McMuffin ( 12 grams of protein). If she had eaten a single serving size container of yogurt at home, she would have eaten 12-15 grams of protein (with fewer calories).

The proliferation of protein bars, some containing more than 20 grams of protein, may be a commercial response to the perception that it is inconvenient to rely on meals to supply enough protein. Protein and vitamin-fortified drinks are being advertised as another convenient source of protein. Such drinks used to be only for people unable to eat regular meals for medical reasons, but are now advertised for anyone not getting enough protein during the day. One such drink made by an international food company contains, in an 8-ounce serving, 15 grams of high-quality protein and 26 vitamins and minerals.

Protein powders are another concentrated source of protein and are available in dozens of varieties. Many are even gender-specific, although of course protein itself is not. Advertised as important for muscle building and weight loss, protein powders are often added to low-protein foods like oatmeal, or put in fruit or vegetable-based smoothies, to increase their nutritional completeness. These highly concentrated sources of protein are made from whey, a high-quality milk protein, pea powder, a good source of protein, and other animal and plant sources.

Getting enough protein should be easy on a conventional diet. If my friend ate two eggs (12 -14 grams of protein), three ounces of salmon (22 grams of protein,) ½ cup of tofu (10 grams of protein), 1 cup of quinoa (8 grams of protein), and one single-serving container of yogurt (12 grams of protein), she would be getting protein that she needs each day. Eliminating animal sources of protein, and following a vegetarian or vegan (no dairy or eggs) diet requires making sure that a plant protein source low in a particular amino acid is not the only source of protein eaten throughout the day.  Moreover, it is really important to look at quantities of protein-rich plant foods in a list of ingredients in a recipe. If 15 ounces of red beans and 3 cups of tofu are in a dish that serves four, unless you eat the entire dish yourself, you may be shortchanged on the protein.

Protein powders are a reliable source of protein (in small quantities.) A scoop usually contains about 20-25 grams of protein and can be sprinkled on top of food or mixed in a beverage. Should a vegetarian, and especially a vegan, diet make getting enough protein difficult, especially when eating away from home, using the protein powder as a supplement may be a solution.

References

“Low Dietary Protein Intakes and Associated Dietary Patterns and Functional Limitations in an Aging Population: A NHANES Analysis,” Krok-Schoen J, Price A, Luo M et al, The journal of nutrition, health & aging 2019; 23: 338-347.

“Amino acid, mineral and fatty acid content of pumpkin seeds (Cucurbita spp) and Cyperus esculentus nuts in the Republic of Niger,” Glow RH, Glow RS, Chuang L et al, Plant Foods Hum Nutri 2006; 61:51-6.