Can You Have Too Much Vitamin B?

Can You Have Too Much Vitamin B?

Taking excessive supplements of vitamin B6 and B12 may be putting your health at risk.

To look like Chris Hemsworth in two Thor films, his stunt double Bobby Holland Hanton reportedly ate 35 times a day—sticking with grilled chicken, turkey, spinach, nuts and boiled eggs. Even he says that’s over the top.

But you don’t need to be a superhero to overdo your quest for a more fit body. Even postmenopausal women can end up over the top—and in peril—by taking excessive supplements of B6 and B12.

An international team of researchers looked at data on more than 75,000 women from 1984 to 2014. Among the 2,304 who had hip factures, the women whose intake of both vitamin B6 and B12 was the highest (35mg/day of B6 and 20mcg/day of B12) were at an almost 50 percent increased risk of hip fracture! Those doses are 20x the 1.5mg recommended daily allowance (RDA) for B6 and more than 8x the 2.4mcg RDA for B12.

How’d they get so much? Well, one popular multivitamin for older adults that we looked at delivers 250 percent of B6 and 833 percent of B12. So, if you take a daily multi-vitamin, aim for one with doses close to the RDA’s and enjoy foods that promote red blood cell and nerve health (B12) and metabolism of proteins, lipids and carbs, cognitive development and immune function (B6).

Foods sources of vitamin B12 include:

  • Salmon (1 serving=80 percent/RDA)
  • Tuna
  • Fortified cereals
  • Low-fat yogurt
  • Low-fat milk

Food sources of Vitamin B6 include:

  • Chickpeas (1 serving=55 percent of the RDA)
  • Salmon
  • Chicken breast
  • Fortified cereals
  • Non-citrus fruits
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