Page 20 - Today's Dietitian (March 2020)

Drawbacks of Plant-Based Protein Powders
While there are benefits to consuming plant-based
protein powders, there are some concerns. Many
products are sold at high price points; they can con-
tain plant protein blends and a variety of added
sweeteners, vitamins, minerals, antioxidants, and
herbal formulations. Clients will need to read labels
carefully to ensure they’d get the amount of protein
they need and that the product meets their health
goals without overconsuming any ingredient that
could interact with a medical condition, medication,
or supplement.

High Costs
When compared with whole food–based protein
options, plant-based protein powders can be expen-
vegetable powders, sweeteners, and flavors. Lim- sive. For example, a block of tofu costs approximately
iting amino acids in blends are harder to assess $1.79 ($0.13/oz); one serving (84 g) contains 80 kcal
because of the variety of ingredients. Beans usu- and 9 g protein. Many plant-based protein powders
ally are limited in methionine, and grains com- cost more than $1 per oz. Instead of buying a plant-
monly are limited in lysine. However, there’s no based protein powder, Wolfram suggests clients con-
need to worry about limiting amino acids in plant- sider adding soymilk, peanut butter, and ground
based diets as long as the diet generally has vari- flaxseeds to a smoothie.
ety. The body has stores of amino acids and can
make what it needs. Possible Contaminants
Another consideration about plant-based protein
Benefits of Plant-Based Protein Powders powders is their safety profile. “Some folks have
Protein powders may be appropriate and beneficial expressed concern over arsenic in rice-based pro-
for some clients. People with increased protein needs tein powders,” Wolfram continues. In 2018, the Clean
such as older adults, athletes, or those with certain Label Project conducted a protein powder study of
illnesses such as cancer, HIV/AIDS, lung diseases 134 top-selling animal and plant-based protein pow-
including COPD, and heart failure, or anyone with ders from 52 brands. They found that organic prod-
hypermetabolism, could benefit from an added protein ucts contained more than twice the amount of heavy
8,9
source. “Protein powders have always been big metals, including lead, arsenic, and cadmium, than
among athletes, both professional and recreational,” nonorganic products tested. They also concluded that
Wolfram says. “While it’s true that protein powders the plant-based products tested generally were more
aren’t necessary to get enough protein, they can be contaminated, while those containing egg as a pro-
helpful when life gets busy. I find that pregnant people, tein source had much fewer contaminants. 10
especially vegans, also take an interest in protein Recent studies on arsenic in rice have caused con-
powder, as protein needs increase in the second and sumers to question the use of brown rice protein in pro-
third trimesters. Especially if a pregnant person has tein powders. The World Health Organization has set
food aversions, sometimes a smoothie with protein maximum tolerable levels for arsenic in drinking water
powder is all they can stomach.” at 10 mcg/L. Arsenic content of raw rice can range
Protein powders also can be useful for patients from 0.1 to 0.4 mg/kg of dry mass—a higher arsenic
interested in general health and wellness. Just one level than other grains. The arsenic is concentrated in
or two scoops of protein powder, depending on the bran layers, so it’s higher in brown rice than white rice,
serving size and type of protein blend, can contain though levels vary widely based on cultivation location
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more than 20 g. Using the Dietary Reference Intake and processing. Arsenic in protein powder may be a
of 0.8 g of protein per kg of body weight, a 150-lb concern depending on how clients consume it, their
person needs about 54 g protein per day. Using pro- overall diet quality, and exposure to this element.
tein powder in a breakfast smoothie or as a snack
could meet about one-third of their needs for the day. Soy
“Plant-based protein powders can help people meet Other consumers continue to fear the safety of soy.
their protein needs in a convenient way,” Wolfram Some studies show that soy supplements contain
says. “For instance, if someone struggles to eat a bal- higher levels of the isoflavones genistein and daid-
12
anced breakfast, or struggles to eat breakfast at all, zein than whole soyfoods. However, it’s unclear
a smoothie with calcium-fortified plant milk, fruit, that these cause any negative effects. A review of 92
greens, and plant-based protein powder can be a randomized, controlled trials (n=9,692) concluded
nutritious and convenient option.” that phytoestrogen supplements don’t have unsafe

20 TODAY’S DIETITIAN • MARCH 2020