Too much B3 on whole food diet

Mathsjunky

Hi there - I need to eat quite a lot of calories for maintenance, typically over 3000. I also look for a large protein intake (c.120g) to support my exercise.

If I'm not very careful it's very easy to go over the upper limit for B3. 100g of chicken and a medium sized baked potato already brings me to 100 of the RDA. Add in 40g peanuts, 30g sunflower seeds and some sweet potato and I'm knocking on the door of the upper limit.
I'm generally very fit and healthy. If I take out meat and swap for veg based protein then I end up going way over the manganese upper limit.

How worried should I be about these upper limits, it seems all too easy to go over them if I'm eating a lot of calories.

cheers
Paul.

Karen_Cronometer

Hi Mathsjunky,

The UL for niacin applies to synthetic forms obtained from supplements and fortified foods only. The type of niacin naturally occurring in foods does not contribute to toxicity symptoms.

There's not as much data on manganese, so the upper limit was set based on the principle of 'no-observed adverse effect' i.e. the highest dose where no harmful effects were seen on a typical Western diet. You can do a deep dive on how the UL for manganese was determined here: https://www.nap.edu/catalog/10026/dietary-reference-intakes-for-vitamin-a-vitamin-k-arsenic-boron-chromium-copper-iodine-iron-manganese-molybdenum-nickel-silicon-vanadium-and-zinc

Best,

Mathsjunky

Thanks Karen - that's reassuring! I won't worry too much about blowing out the niacin with whole foods then, but I'll keep a lid on the manganese. I can easily do one or the other, but keeping both in check is hard work.
Paul.