PROTEIN POWDERS

PROTEIN POWDERS By Toby Amidor, MS, RD, CDN
Q: Many of my clients purchase protein powders. What are the main types available and the guidelines for recommending them?
A: There are several varieties of protein powders, including those derived from milk, soy, eggs, and rice. Before recommending any protein supplement,however, it’s important to determine if your client really needs one.

The Types
Dairy Based

 Both casein and whey protein powder supplements are derived from milk. Casein is a milk protein isolate known as caseinate that provides 22 g of protein per ounce and takes longer to digest than whey. A 2011 study in the American Journal of Clinical Nutrition found casein supplementation didn’t stimulate postprandial muscle protein accretion as effectively as whey.1 However, a 2007 study in Amino Acids found the combination of both casein and whey to be more effective in improving body composition and muscle strength.2 Whey protein is the most common protein powder sold. It’s more easily absorbed and helps build and maintain muscles. It’s found in concentrate or isolate form. Whey protein concentrates are less expensive and contain between 30% and 85% protein, while whey protein isolates contain at least 90% protein and provide 24 g per ounce. The isolate form is more easily absorbed but is typically more expensive. Since casein and whey protein are derived from milk, don’t recommend them to clients who are lactose intolerant or have milk allergies.

Soy Based

This protein is derived from soy flour and is appropriate for those with allergies or who follow a vegetarian or vegan diet. It’s available as an isolate or concentrate; the isolate form is purer and more expensive and provides 15 g of protein per ounce. Studies have shown that soy protein helps lower LDL cholesterol.3 Clients may voice concern about the hormonelike compounds found in soy; however, studies have determined that up to 60 g of soy protein per day is safe.

Additional Varieties

Other protein powders from eggs, rice, peas, or hemp are available. Egg protein is derived from egg whites, is free of both fat and cholesterol, and is easily absorbed. It contains 21 g of protein per ounce. Rice protein is derived from brown rice and contains 18 g of protein per ounce. Pea protein contains 20 g of protein per ounce, while hemp provides 12 g. Rice, pea, and hemp (plant-based protein powders) have essential amino acids added and are good alternatives for those with allergies or clients who follow a vegetarian or vegan diet.

Protein Recommendations

The Recommended Dietary Allowance for protein is 0.8 g/kg of body weight (or 0.36 g/lb of body weight). On average, this amounts to 56 g/day for men and 46 g/ day for women aged 19 and older. Most individuals can obtain this amount of protein from diet alone and don’t require protein supplements. Typically, protein

supplements aren’t needed for clients who exercise a few times per week for an hour or less. If clients insist on using a protein supplement, calculate their protein needs and compare them to how much they’re currently getting to ensure they achieve a proper balance between food and supplement use. Clients also should understand that protein powders are neither inferior nor superior to protein derived from food, but they’re pricey and lack certain nutrients found in whole foods.

Cautions

Protein powders shouldn’t contain added vitamins, minerals, and herbal supplements because they can interact with various medications, including antibiotics, levodopa used in Parkinson’s disease, and alendronate used to treat osteoporosis. In addition, synthetic amino acids sometimes are added to protein powders. Scientific evidence is inconclusive as to whether adding more amino acids to protein powder formulations is better. Consuming too much protein can lead to dehydration and is contraindicated in those with renal issues. Side effects of large doses include nausea, thirst, cramps, bloating, headache, and

upset stomach.

— Toby Amidor, MS, RD, CDN, is founder
of Toby Amidor Nutrition, a nutrition expert
for FoodNetwork.com, and a nutrition
advisor for Sear’s FitStudio.