"Plant milk" is a category that covers drinks as different as soy (which is nutritionally close to cow's milk) and rice milk (which is essentially a sugar-water smoothie with a splash of starch). The label alone won't tell you which is which — but a few numbers will.
Protein is the big split
Cow's milk has about 3.3 g of protein per 100 ml. Among plant drinks:
- Soy — around 3–3.5 g/100 ml. Genuinely comparable.
- Pea — around 2–3 g/100 ml. Also solid.
- Oat — around 0.5–1 g/100 ml. Much lower.
- Almond — around 0.5 g/100 ml. Very low.
- Rice — around 0.1 g/100 ml. Basically none.
If you're swapping out cow's milk for a cappuccino, any plant milk works — you're not relying on the milk for protein. If you're using it in a kid's breakfast cereal as a protein source, soy and pea are the only real swaps.
Added sugar sneaks in
Unsweetened plant milk is usually just plant + water + a pinch of salt. Sweetened versions can contain 4–7 g of sugar per 100 ml — comparable to a soft drink. The difference between "original" and "unsweetened" on the carton is usually just added sugar.
Rule of thumb: if you see more than 2 g of sugar per 100 ml and the ingredients don't include actual fruit, it's added sugar.
Fortification is your friend
Cow's milk is naturally high in calcium, B12, and iodine. Plant milks have none of those unless they're deliberately added. Look for:
- Calcium — target 120 mg/100 ml (what cow's milk provides).
- B12 — usually listed as µg per 100 ml.
- Vitamin D — often added.
Fortified plant milk is a completely reasonable nutritional swap. Unfortified plant milk isn't. The same "oat milk" brand can sell both.
The short version
- Want the closest nutritional swap for cow's milk? Fortified unsweetened soy or pea.
- Just want something for coffee? Anything works.
- Avoid rice milk and unsweetened almond milk if this is a main protein source for a child.
None of this is new science — it's just usually buried in a nutrition table most shoppers never read. That's what Nourisk is for.