Editor’s Note: Every week, we receive hundreds of emails from all of you. Sometimes, you ask us to go a little deeper to help you understand topics. We save these longer emails on one topic for the weekend.

You already know protein matters. If we’re being honest, even if you didn’t, when you walk into a grocery store these days, you see protein highlighted on everything; it wouldn’t take long to figure out you need protein. 

But what about powders? There is no shortage of options, and that’s part of the problem.

Whey, casein, isolate, hydrolysate, soy, pea, egg. Grass-fed, fermented, pre-digested. Hundreds of brands, each one insisting it’s the difference between progress and wasted money.

A simple purchase starts to feel like a research project you never signed up for, and the easiest thing to do is freeze, grab whatever’s on sale, and wonder later whether you got it wrong.

So let’s clear the clutter. 

Last week, when we mentioned Momentous’s “once in a lifetime” sale for 40% off everything on their site, we got a lot of questions. Not just about why we recommend Momentous, but about what we specifically look for in a supplement and what the research shows. 

In other words: take away the brand name on the front, and when we look at a label, how do we determine if something is quality? And what really works?

Most of the questions we received were about protein, so we built this weekend report around the most common questions you’ve asked us. By the end of this email, you’ll know what to grab and, just as useful, what you can stop worrying about.

One promise up front: it’s a lot simpler than the marketing wants you to believe.

Do You Really Need Protein Powder?

Here’s what the supplement industry won’t lead with. 

Protein powder is not magic. 

It’s convenient. And if you get the right one, it’s a high-quality nutrition option.

Matched gram for gram, a scoop of whey and a chicken breast do roughly the same thing for your muscles. The powder isn’t better than food. It’s faster, cheaper per gram, and it fits in a bag. 

It turns “I should eat more protein” into something you can pull off on a chaotic Tuesday.

That’s the whole job. A powder is a tool for hitting your daily protein number when food alone is a hassle.

And that number is the real lever. Research on people who train converges on about 1.6 grams of protein per kilogram of body weight per day to build muscle, with the benefit flattening out around 2.2 g/kg.

To be clear, that doesn’t necessarily mean more protein is better. It just means that studies have shown that 1.6 g/kg helps you build muscle, and others suggest you might continue to get benefits up to 2.2 g/kg. View it as a range that offers flexibility to make your diet work for you. 

If you need help figuring out how much this is, here’s the easy math: take your weight in pounds, divide it roughly in half, and that’s a solid daily target in grams. An 180-pound person is aiming for roughly 90 to 180 grams of protein per day. 

Yes, it’s a big range. But instead of viewing that as a frustration, see it as an opportunity to play around with the amount of protein that works for you and helps you hit your goals. 

Remember, protein is just one macronutrient. As we teach people in the Pump Club app with the nutrition tracker, all the nutrients work together. You adjust your protein up or down, and then you can adjust how many carbs or fat you eat. 

So, having a range gives you more flexibility to adjust the dial, enjoy your diet, and see results.

Powder exists to help you close the gap between that target and what you’d otherwise eat. Find one that does that reliably, and you’ve already won most of the game.

The only other thing that matters per serving is leucine, the amino acid that flips the switch on muscle building. You want about 2-3 grams per scoop. Nearly every decent powder clears that bar in a normal serving without making a fuss, so file it away. We’ll come back to it when it changes a decision.

Everything from here is just choosing well.

Which Type Of Protein Is Right For You?

There are so many protein options, but as you filter through the labels and the science, you can boil it down to four great options. Other options can work, but they require more expertise and nuance in reading labels, which just adds complexity and stress.

Here’s the fast version, then the reasoning.

If you have no dietary restrictions: whey isolate or whey concentrate
Why: Cheapest high-quality protein, fast, high in leucine

If you want a “cleaner” protein with fewer calories (fat and carbs) or have a lactose sensitivity or allergy: Whey protein isolate
Why: Essentially no lactose, carbs, or fat. 

Dairy is not an option: Pea + rice protein or soy or potato protein (potato is, admittedly, very hard to find)
Why: You can’t have anything with milk, and these have the best, most complete amino acid profiles, similar to whey-based.

You want a more filling shake but not all the calories: Casein
Why: A slow-release protein that creates a much thicker shake. 

High-quality protein that is not dairy but also not plant-based: Egg protein
Why: Egg protein is very similar to whey, but dairy-free.

Now the why, because “why” is what stops the second-guessing.

Whey: the default, and there’s no shame in defaulting

Whey is the most-studied, fastest-digesting, highest-leucine protein you can buy. For most people, the conversation could honestly end right here. It works, it’s affordable, and your body handles it well unless dairy is a problem for you.

Plant: better than its reputation

For years, the case against plant protein rested on two facts that were true but got stretched too far. Plant sources tend to run lower in leucine, the amino acid that triggers muscle building, and your gut absorbs slightly less of what they deliver. 

Measure the muscle-building spike right after a single shake in a lab, and animal protein looks clearly ahead. That snapshot is where the “plant protein can’t build muscle” reputation was born.

The problem is that a one-shake spike in a lab isn’t the same as muscle built over months of training, and when researchers measure the thing that matters, the gap shrinks fast. 

A 2025 review that pooled 30 controlled trials found only a small overall edge for animal protein in muscle mass, and no meaningful difference in strength or physical performance. Look at soy or pea protein on its own and even the muscle-mass gap against dairy was essentially nothing. In older adults specifically, it washed out entirely.

Translation: if you’re dairy-free, plant protein is not a consolation prize. It holds its own.

Why does the old gap mostly vanish in the real world? Largely because your daily total does the heavy lifting. 

Once you’re eating enough protein across the day, the small per-serving differences between sources stop adding up to anything you’d notice in the mirror. Source matters most when protein is scarce and least when it’s plentiful, which, for most people, it easily is.

The honest caveat is that not all plants are equal. The animal edge the review did find came from single non-soy sources like rice, oat, and potato, each one short on an amino acid when eaten alone. That’s a solvable problem, not a dealbreaker. 

Pea is low in methionine; rice is low in lysine, which pea has in spades. Blend the two, and you end up with a profile that looks like whey. Soy, meanwhile, is the rare single source that’s close to complete on its own, which is why it keeps turning up in products. 

And the lingering fear that soy lowers testosterone or “feminizes” men? It hasn’t survived controlled research at normal intakes. Let that one go.

Egg: the underrated dairy-free pick

Excellent quality, fully dairy-free, easy on most stomachs. One quirk worth knowing: egg white runs a little low on leucine, so you nudge the serving up slightly. A great fit if milk-based powders don’t sit right with you.

Casein: the slow one with a narrow job

Casein digests slowly and keeps you full for hours, which makes it a smart choice before a long stretch without food. It is not overnight muscle magic, whatever the label implies. Think satiety and convenience, not a separate tier of gains.

What To Look For Once You’ve Picked A Type

This is where people overspend on details that don’t move the needle. Quick guide.

Buying whey? Should you go with concentrate, isolate, or hydrolysate?

You’ll see three versions sold like rungs on a quality ladder. The ladder is flatter than it looks.

Concentrate is the least processed and the cheapest, with a little lactose and fat left in. Perfectly good if dairy doesn’t bother you. It usually comes with a higher calorie count, more sugar, and some variability as to how much protein you’re actually getting. Because concentrate is not standardized, the protein content can range from roughly 30% to 80%. 

Isolate is filtered further, so it’s leaner with almost no lactose. Plus, isolate tends to be standardized at 85 to 90 percent pure protein (or more). It’s our go-to option because it checks a lot of boxes: easier on the stomach, lactose-friendly, great for those watching calories, lower in fat, carbs, and sugar, better mixability, and, for us, worth the small premium.

Hydrolysate is “pre-digested” for faster absorption and a faster way to empty your wallet, as it carries a 40-to-70% markup. The honest truth: that speed buys nothing you’ll notice. 

For nearly everyone, it comes down to this: isolate is the go-to, concentrate if your stomach handles everything great and you want to save a little bit. 

While we’re here, the panic about slamming your shake within 30 minutes of training is overblown. A 2023 study fed trained men 100 grams of protein in one sitting and observed a larger, longer muscle response than with 25 grams, with no sign of a ceiling and no evidence that the extra went to waste. The window is measured in hours, not minutes. Hit your daily total and timing mostly takes care of itself.

Buying plant? We Have You Covered

Two rules and you’re done. Choose a pea-and-rice blend or soy over a single non-soy plant. If you can find it, potato protein is also a solid option, but usually needs to be combined with another plant protein source. 

And take a slightly bigger scoop, roughly 25% more, or a double scoop. Most plant proteins run a touch lower in leucine. It’s not a problem or a flaw; it’s just a reality. So to account for that, taking a little more protein evens things out, and the plant powder performs right alongside whey.

The Fine Print That Matters

We don’t want you to spend all day looking at labels, but when reviewing the labels, there are a few red flags that can help you avoid bogus powders that are trying to deceive you, which means who knows what else may (or may not) be in the powder.

After all, remember, supplements — unless they are third-party certified — do not need to prove that what’s on the label is actually in the product. It’s not uncommon for protein powders to claim 20 grams of protein and have much less upon further testing. 

Without sending a supplement to a lab, here are a few ways to scan a label and identify products to avoid. 

Red flags on the label

The sketchiest trick in the business is amino spiking. Protein content gets estimated by measuring nitrogen, and a few cheap ingredients (free glycine, taurine, even creatine) happen to be nitrogen-rich. So a company can toss those in, inflate the protein number on the label, and charge you for protein that isn’t really there. It was common enough a decade ago to trigger a wave of class-action lawsuits.

You can’t taste it. But here’s how you can determine if a brand is spiking their powder to mislead you:

• Free amino acids like glycine, taurine, or glutamine listed in a basic protein powder

• A vague “amino blend” or “proprietary blend” with no individual amounts shown

•  A price per gram of protein that looks too good to be true

What good looks like is the opposite of all that: a brand that publishes a full amino acid profile with the leucine listed, names every ingredient and its amount, and gets verified by an outside lab.

Heavy Metals (No need to panic — and a way to limit exposure)

This is the headline that scared many people, so here’s what you need to know, why some claims are overblown, and why some powders are better than others.

In early 2025, a nonprofit called the Clean Label Project tested 160 popular powders and reported that 47% topped California’s strict Proposition 65 limit for at least one heavy metal. 

Plant powders averaged about 3 times the lead of whey, since plants pull metals up from the soil. Organic wasn’t cleaner. Chocolate was the worst flavor.

Now the part that didn’t travel as fast. “Over Prop 65” is not the same as “dangerous in a scoop.” Prop 65 is the strictest standard in the country, set far below federal limits. It is well beyond European safety standards.

The report wasn’t peer-reviewed, an industry group disputed its methods, and the organization that ran the testing also sells the certifications it recommends, which is worth knowing.

Here’s the calm response, not the fearful one: Buy a protein that is third-party tested, which on its own clears up most of the concern. 

A product that is NSF Certified For Sport (look specifically for “Certified For Sport”) cannot contain dangerous levels of heavy metals. It’s the peace of mind you really want. 

Your body can handle heavy metals. They are found in water, vegetables, and many perfectly healthy foods. That’s not to say they are completely benign but that they are naturally occurring. And research doesn’t show that all exposure is a threat.

The real goal is to limit heavy metals where you can. 

So start with third-party-certified powders, and you should be good regardless of the type.

However, if you’re truly worried, use a whey or egg-based protein. And if you want to reduce exposure even more, pick a non-chocolate flavor, such as vanilla, strawberry, or even unflavored.

The Certifications Worth Trusting

This is the single most reliable signal of a clean, honest product, so it’s worth memorizing the names: NSF Certified for Sport, Informed Sport, and BSCG. Each one means an independent lab checked that the label is accurate and screened the product for contaminants and banned substances. 

But it’s not just what they test for; it’s what they demand of brands. 

With NSF Certified For Sport, you can’t just send over a single sample and then sell a bad lot. Entire batches must be tested to carry the label, ensuring consistent manufacturing and peace of mind that the tub you purchased is safe.

In an industry where it’s almost too easy to lie about what’s in a product, that seal is the closest thing to a guarantee you’ll get.

The Protein Myths

Any time we talk about protein, we get many people who are worried about health concerns, so let’s address the most common fears that are not based on science.

Fear #1: “Protein wrecks your kidneys.” 

Not in healthy people. 

In fact, in one study, men eating more than 3 grams per kilogram for a full year showed no harm to kidney function. 

The real exception: if you’ve been diagnosed with kidney disease, follow your doctor’s guidance.

Even then, some studies suggest higher protein is helpful. But if you have a health condition, you should be working with your physician to figure out what your body needs. 

Fear #2: “It’ll make me bulky.” 

Protein is food, not a drug. Building noticeable muscle takes years of hard training. A scoop just helps you recover and provides your body with amino acids for other critical functions, including keeping your hair, skin, and nails healthy.

Bulk comes from many factors, including a high calorie intake. 

A scoop of protein powder typically contains 100 to 150 calories. This will not make you bulky. It doesn’t happen that easily.

Fear #3: “My stomach can’t handle it.” 

Usually, protein itself isn’t the irritant. It’s what else is stuffed into the powder.

For some, it’s lactose, which is why alternatives exist.

For many, it’s the sweeteners. In particular, many protein powders use sugar alcohols (sweeteners ending in “-itol,” such as maltitol, sorbitol, xylitol, or sucralose) or added gums. These ingredients are known to cause GI issues, gas, or bloating. 

Switch to a simple isolate or plant formula, opt for sweeteners such as stevia (sometimes listed as Reb A, Reb B, Reb M) or monk fruit, or even a couple grams of natural sugar, and the trouble often vanishes.

So, What Makes A Good Protein Powder?

If your eyes glazed over somewhere around “hydrolysate,” we want to make it clear what works.

We love Momentous for one simple reason: they have a higher standard for quality, purity, testing, and effectiveness. Not because it’s flashy or because we’re sentimental about it, but because it checks every box that matters:

High-quality protein. Grass-fed whey isolate that’s complete and high in leucine, plus a plant-based version if you’re dairy-free, and both are certified.

Tested twice over. NSF Certified for Sport with lab results and a Certificate of Analysis published for every batch. You can look up the exact jar in your hand.

No amino spiking or proprietary blend. Full transparency, confirmed by those same tests.

Low on contaminants. Whey-based and batch-tested, with the numbers posted rather than promised.

A clean formula. No gums, no artificial sweeteners, no filler.

It tastes good. The box everyone forgets, and the one that decides whether the tub gets finished or shoved to the back of the pantry.

It is not the cheapest powder on the shelf, and we’re not going to pretend it is. What it is: one of the few that passes every test you’d otherwise have to run yourself. If you’d rather have a single answer than a decision tree, that’s a fair place to land.

But let’s be honest about something else: because we live in a GLP-1 universe, the cost of protein (specifically whey) is skyrocketing. So the entire industry is facing increasing costs of whey, and whey powders are getting more expensive.

The good news: Momentous is on sale for 40% OFF everything.

The sale is only live for another 48 hours, so you can stock up on protein, creatine, Fiber+ (which we formulated and developed), fish oil, or anything else you need. 

The 60-Second Checklist

Before you buy, run down this list. You don’t need every box perfect. You need to know what you’re trading.

• 20 to 30 grams of protein per scoop, relative to the scoop size

• A full amino acid profile listed

• No proprietary blends hiding what’s really in the product. 

• No free amino acids like glycine, taurine, or glutamine listed in the ingredients

• A short, recognizable ingredient list. If you have GI issues, no artificial sweeteners

• Third-party tested: NSF Certified for Sport, Informed Sport, or USP

That’s the whole thing. 

Remember, you don’t need a protein powder, but it makes it a lot easier to hit your protein goals.

And at the end of the day, how much protein you eat a day matters far more than the source, the timing, or the frequency. 

Everything else is just there for people to debate. Save yourself the stress and confusion, and stop majoring in the minor. Use the guide above, and find the best option that works for you.

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Publisher: Arnold Schwarzenegger​

Editors-in-chief: Adam Bornstein and Daniel Ketchell