Protein in a mass-building or get-lean diet is a lot like a 401(k) plan: You know you need it, but you’re not always sure which one to pick. Just as diversifying your investment portfolio is crucial to long-term wealth, so too is including a variety of different proteins in your daily meal plan. The proteins found in whole foods, like beef, poultry, fish, and dairy are vital, but so are those found in protein powders, bars, and ready-made shakes. The problem is there are as many options as there are 401(k)s. That’s why we’ve put together a guide to help you navigate your way through the different tubs, bars, and shakes available in the marketplace today.

Protein Bars

Assuming you don’t have the time (or desire) to prep every meal and snack, convenience is a big deal. That’s where meal-replacement bars come in handy, as they’re much more physique-friendly than anything you’ll find at fast-food chains and convenience stores. If you’re hurrying out the door for work, throw a bar in your bag. If you’re afraid of getting stuck in the office with nothing healthy to eat, keep a box of bars at your desk. Most bars on the market these days include protein, fats, and carbs, making for a small meal to tide you over until the next meal. Plus, there are a number of low-carb bars available that include sugar alcohols, which aren’t readily absorbed in the body like regular sugars. Because the protein doesn’t absorb as fast as in liquid form, bars aren’t ideal for pre- and post-workout, but they’re fine to include in your diet in moderation.

Ready-to-Drink Shakes (RTDS)

Once again, when talking convenience, RTDs are very low-maintenance. Just crack the top and drink. Like bars, RTDs travel well and can be stored easily at work, but they’re always better refrigerated. Though not a horrible choice around workouts, RTDs still aren’t your best bet before or after training, as they typically contain milk protein, which is 80% casein (slow-­digesting). If possible, save RTDs for snacks.

Casein Protein

Casein is great before bedtime for providing a steady trickle of aminos during your overnight fast, and it’s even been found to enhance muscle building when added to whey in a post-workout shake. Look for a powder that includes micellar casein, the slowest-digesting casein of them all, though forms listed as ­“caseinates” are good as well.

Whey Protein

When it comes to building muscle, nothing beats whey. It’s the ideal protein for stimulating muscle growth before and after workouts. The best whey powders on the market contain whey protein isolate and/or whey protein ­hydrolysates—these are the purest forms of whey, the ones that digest the quickest and get to your muscles ASAP. For your basic supplement regimen, start with a protein powder that’s either 100% whey or a blend that lists whey as its first ingredient.

Milk Protein

Take out most of the carbs and fat in milk, and you’ve got a product known as milk protein. As mentioned earlier, milk protein is 80% casein, 20% whey, so it’ll be relatively slow digesting and therefore better around bedtime and as a snack than before or after workouts. However, a mixed protein powder that includes milk protein can still be fine pre- and post-workout, so long as whey is listed before it on the ingredients list. And when shopping, look for the words milk protein isolate, which designates its purest form, or milk protein concentrate.

Egg White Protein

Before whey was discovered, this was the bodybuilder’s protein of choice. Egg white protein is very high quality, and in terms of speed of digestion, it’s slower than whey but faster than casein. So while on its own it’s not the best around workout time, a mixed powder containing egg white, whey, and casein protein can be effective at virtually any time of the day. In this case, you’ll be diversifying with fast-, slow-, and medium-digesting proteins to feed the muscles in both the short term and long.

Beef Protein

Rest assured, we’re not talking about beef bouillon cubes here or anything, for that matter, that tastes remotely like red meat. (Ironically, it comes in fruit flavors.) Beef protein powder, as the name implies, comes from actual beef that’s had nearly all of its fat stripped away. As a ­result, it digests very quickly, making it a worthy substitution for whey for those who have a milk protein allergy.

Soy Protein

While soy protein isolate is fairly fast digesting (not quite as fast as whey), it’s real benefits come from the fact that it has been shown to boost nitric oxide levels, increase growth hormone release, and aid muscle recovery following workouts. And if there is still any doubt about its effects on testosterone and estrogen levels, let us confirm that the latest research concludes that soy does not decrease testosterone or raise estrogen levels in men.