A new study from Finland - by Tilli et al. 2026 (University of Helsinki) - found that among 34 vegan adults, 28 (82%) supplemented iodine. The authors estimated that median iodine intake in vegans was about 109 (87–152) µg [median and 25th–75th percentiles].
They also report that four vegans (28%) took omega-3 supplements.
The authors conclude:
"[...] continued efforts are required to support individuals following [vegan and vegetarian] diets, as the exclusion or reduction of animal-source foods, if not accompanied by appropriate dietary knowledge about key plant-based sources of critical nutrients, may increase the risk of inadequate intakes. Of particular concern are iodine and long-chain n-3 fatty acids."
I think this conclusion is largely accuarate, at least for vegans - but the last sentence seems quite inaccurate.
In contrast to most previous studies, this study showed that estimated iodine intake was close to the recommendations - which are not totally non-controversial - and therefore, quite close to adequate. However, the authors may mean that iodine is of concern - although their study did not show this. This is true.
That a direct intake of long-chain omega-3 fatty acids - i.e., EPA/DHA supplements for vegans - are beneficial is highly controversial, particularly for vegans with reasonably healthy diets and a relatively high intake of alpha-linolenic acid (ALA). ALA intake in this study was estimated to be about 3 to 6 g per day in the adult vegans - 1 tablespoon of flaxseed oil has about 7 g of ALA.
So the idea that long-chain n-3 fatty acids are of "particular concern" remains a controversial claim.
