Oats have long been considered a simple, respectable health food for the masses. But are they really such a wonderful food, or is their status as a humble superfood a myth that needs to be smashed? Let’s take a look.
Let’s start with some well controlled studies with favorable outcomes for oats:
1. In one study, older men ate about 1 1/2 cups of oats for 12 weeks (). By the end of this period the men eating the oats had lower small (bad) LDL, higher large (arguably good) LDL, lower triglycerides, lower VLDL, a better total: hdl cholesterol ratio, and lower fasting insulin. This study did the same thing with wheat. Wheat made most of these values worse.
2. In another study (), adding oats to the diet of hypertensive and hyperinsulinemic people led to lower blood pressure, lower LDL, lower triglycerides, and a trend towards improved insulin sensitivity.
3. Compared to a control diet, oats were better for blood pressure and insulin sensitivity (). The control diet basically had wheat instead of oats.
4. One study fed 88 hypertensive individuals either oats or refined wheat for 12 weeks (). At the end of the study the oats group had lower LDL cholesterol, lower blood glucose levels, and notable improvements in their blood pressure (enough for many in this group to stop or reduce their BP medication).
Do these studies mean oats are good? Not exactly. Compared to crap food like wheat, almost certainly. But how are they compared to nutrient dense health foods? I haven’t been able to find studies comparing oats to things like eggs, fruits, or tubers so I can’t say for sure.
Phytic acid is the main problem I have with oats. On it’s surface, oats are a good source of nutrients. But they have tons of phytic acid (and some other anti-nutrients), so many of the minerals in oats will have reduced absorption. This includes zinc, iron, calcium, magnesium, and copper (,,). So if you’re eating a lot of oats I’d be really careful to make sure I was getting enough of these minerals.
I also wouldn’t recommend oats to people who have problems with gluten or their intestinal health. A controlled trial () on recovering celiac patients found that those eating gluten free oats increased intestinal problems like diarrhea and intestinal inflammation. My own experience as a gluten intolerant is that oats are bad for my belly.
But back to the good things, I found a study that attempted to measure how subjectively satiating a number of foods were by feeding 240 calories of said food to volunteers who then reported how long it was before they felt hungry again . A porridge made from oats was one of the most satiating foods tested, behind only fish and potatoes. This suggests oats may be a useful controller of appetite.
Ultimately, oats appear to be an pretty good food. They’re especially good in the context of weight loss and heart health, but may be bad during poor gut health and in facilitating the acquisition of adequate amounts of dietary minerals.