Yes, it's best to get all you need, including protein, from real, whole, natural foods. However, to preserve muscle mass during weight loss, to get a quick protein bump timed just after a weight workout or to maintain muscle mass one you get up in years….
Whey is widely accepted as a good supplement for success. Buy smart though - these few paragraphs below are spot on. Brazenly stolen from Eat This, Not That! website - check them out Here
“When you're looking for the proper animal-based protein powder, look out for words like cold processed, concentrate (isolate only if you're sensitive to lactose), hormone-free, grass-fed, tested low for heavy metals, and does not contain sucralose or any artificial color, flavor or sweetener. ( GK - Stevia is cool though )
If you want a "fast acting" protein that will stimulate protein synthesis after a workout, go with whey. While a whey protein concentrate has a lower percentage of protein than whey isolate, it contains more bioactive compounds found in the milk fat that positively influence metabolism and immunity—just make sure it's low-temperature-processed (raw or cold-processed). This method allows the protein powder to retain many of its fragile immune factors and nutrients leaving it loaded with the ideal blend of easily-absorbed amino acids, anti-inflammatory compounds, essential fats, energy-replenishing carbs, metabolism-boosting peptides, potent antioxidants, and alkaline minerals.
You'll get even more of these nutrients when your powder is made from pasture-fed cows, which have a higher concentration of inflammation-reducing omega-3 fatty acids and two to five times more CLA (conjugated linoleic acid) than their corn and grain fed counterparts. CLA provides a variety of health benefits like burning fat and maintaining lean body mass. Besides toning your body, these two sources of dietary fat will also improve absorption of key vitamins and carotenoids. Not to mention, grass fed cows are less likely to be treated with antibiotics than grain fed cows, meaning you'll have a lower risk of building up antibiotic resistance or gaining unnecessary weight.”
Remember - it's a supplement, real food is better, and cheaper ;-)