Oat Milk vs Soy: Which Is Less Inflammatory?
Oat Milk
Soy
Soy is less inflammatory than oat milk. On the plant milk shelf these two are the closest thing to a straight swap, so nothing about your morning has to change.
Oat milk has a problem built into the way it is made. Enzymes break the oat starch down into sugar during production, so it lifts your blood sugar faster than cow’s milk does, and barista versions add rapeseed or sunflower oil on top to make the foam hold. Soy gives you complete protein instead, as complete as the protein in meat, with fibre and almost no saturated fat. Pour unsweetened soy in your coffee this week and keep the oat carton for the days when soy is off the table.
Side by side
| Oat Milk | Soy | |
|---|---|---|
| Inflammation Score | Medium · 5/10 | Low · 3/10 |
| Category | Beverages | Legumes |
| Serving size | 1 cup (240 ml) | 1/2 cup cooked soybeans (90 g) |
| Key nutrients | Maltose (from enzymes), Beta-glucan, Rapeseed oil (added), Calcium (fortified) | Isoflavones (genistein), Complete plant protein, Fibre, Linoleic acid (soybean oil) |
| How often | A splash in coffee daily, unsweetened rather than barista | Most days, as edamame, tofu, tempeh or miso |
On the AIP diet
Oat Milk
Oat milk is not allowed on the Autoimmune Protocol. It is made from a grain, and the elimination phase takes out every grain without exception. The rest of the carton makes it doubly awkward, because the seed oils in barista versions and the gums that keep it smooth are off the list on their own terms. During the elimination, unsweetened coconut milk is the usual stand-in.
Soy
Soy is not allowed during the elimination phase of the Autoimmune Protocol. Every legume goes in that phase, and soy takes the most with it: beans, tofu, tempeh, miso, soy milk and soy sauce all leave at once. It also comes back late in the reintroduction, if at all. Coconut aminos stand in for soy sauce, and the protein comes from meat and fish.
What each one brings
Oat Milk
- No lactose and no milk protein, so it suits the people that dairy does not
- Some of the oat's soluble fibre survives into the glass, and it brings cholesterol down
- Nut free, which matters when almond and cashew milks are off the table
- Most brands are fortified, giving back the calcium and B12 that leaving dairy takes away
Soy
- Protein as complete as meat, with no cholesterol and little saturated fat
- Fibre that stays with the protein in whole soy and feeds the gut bacteria
- Isoflavones, plant compounds that behave more like antioxidants than hormones
- Tempeh and miso are fermented, so part of the bean is broken down already
Watch out for
Oat Milk
- Enzymes break the oat starch into sugar during production, so it lifts blood sugar faster than cow's milk
- Barista versions add rapeseed or sunflower oil to make the foam hold
- Sweetened cartons pile sugar on top of the sugar the process already made
- It is made from a grain, so it is out during the AIP elimination phase
Soy
- Most soy eaten today arrives as oil or powder inside packaged food
- Soybean oil is the fat behind a lot of fried food
- Soy sauce brings plenty of salt and little of the bean
- A common allergy, so it is always named on the label
Get the inflammation score of any meal
Just snap a photo or describe your food to get its inflammation score and uncover hidden patterns that may be affecting your well-being.
