Walk down any supplement aisle and the tubs make big promises: 20 grams of protein, complete amino acids, zero fillers. Turn one around and the ingredient list often adds gums, artificial sweeteners, anti-caking agents and processing aids. Independent testing has also found measurable lead, arsenic and cadmium in some plant-based protein powders, usually picked up from the soil the crops grew in.

You can make your own in about five minutes, from seeds you probably already trust.

Why make your own

You control every ingredient, you can tune the balance of protein, fiber and fat to your needs, and it costs much less than store-bought. It also tastes fresher than the chalky, oversweetened versions on the shelf.

The building blocks

Pea protein is the base of most plant blends. It’s gluten-free, dairy-free and free of the major allergens, with a solid amino acid profile and some iron. You can buy pea protein isolate, or grind dried split peas at home. Home-ground peas give you pea flour rather than a true isolate, since the protein isn’t separated from the fiber and starch. That’s not a flaw, just a more whole-food product.

Hemp seeds are one of the few plant foods with all nine essential amino acids, plus omega-3 and omega-6 fats, magnesium, iron and zinc. Use shelled hemp seeds (hemp hearts); the shells are too tough to digest comfortably.

Flaxseed is known for omega-3s and lignans. Grind it fresh rather than buying it pre-ground, because the oils go rancid quickly once exposed to air.

Chia seeds add less protein than hemp but lots of fiber, and they thicken shakes nicely.

Recipe: simple three-seed base

• 1/2 cup shelled hemp seeds
• 1/2 cup flaxseeds
• 1/4 cup chia seeds

Put the seeds in a dry, high-speed blender and pulse in short 10 to 15 second bursts, shaking the jar or scraping the sides between pulses. You want a fine, flour-like texture, about like almond flour. Blend too long and the oils release, and you’ll get paste instead of powder, so go slowly. Store it in an airtight jar; a wide-mouth mason jar makes scooping easy.

Storage: because of the natural oils, this keeps about 2 weeks in a cool, dark pantry, up to 2 months in the fridge, or up to 6 months in the freezer. A triple batch in the freezer means you always have some.

Want more protein per scoop?

Stir in pea protein isolate for a big boost without changing the flavor much. Or toast chickpea flour in a dry pan until fragrant, which softens the raw bean taste, and blend it in. For a whole-food pea option, soak split peas overnight, rinse and dry them well, bake at 350°F for 35 to 40 minutes until golden, then grind.

Sample high-protein blend (20+ grams per serving)

• 1 cup green split peas, soaked overnight, rinsed, dried and roasted at 350°F for 35 to 40 minutes
• 2 tablespoons flax meal
• 2 tablespoons chia seeds
• 1 tablespoon sunflower seeds

Let the peas cool completely, blend everything together, then sift out any large pieces and blend them again.

It’s a small thing, but making your own food staples is one way to take care of the body you’ve been given and know exactly what’s in it.

“And God said, Behold, I have given you every herb bearing seed, which is upon the face of all the earth…” (Genesis 1:29, KJV)