When to promote supplement use and when to curb it
High doses of some manufactured vitamins are potentially harmful, say Harvard preventive health experts.
Writing in JAMA, they point out that recent trials suggest that exceeding the recommended daily allowance of beta-carotene, folic acid, vitamin E or selenium is associated with increased mortality, cancer and haemorrhagic stroke.
“Clinicians have an opportunity to promote appropriate use and to curb inappropriate use of micronutrient supplements, and these efforts are likely to improve public health,” write Dr JoAnn Manson and Dr Shari Bassuk.
They have compiled this supplement guide:
|Pregnancy||Folic acid, prenatal vitamins|
|Infants and children||For breastfed infants, vitamin D until weaning and iron from age 4-6 months|
|Midlife and older adults||Some may benefit from supplemental vitamin B12, vitamin D, and/or calcium|
|Bariatric surgery||Fat-soluble vitamins, B vitamins, iron, calcium, zinc, copper and multivitamin/multimineral|
|Pernicious anaemia||Vitamin B12 (1-2 mg/d orally or 0.1-1mg/mo intramuscularly)|
|Crohn's disease, other inflammatory bowel disease or coeliac disease||Iron, B vitamins, vitamin D, zinc and magnesium|
|Osteoporosis or other bone health issues||Vitamin D, calcium and magnesium|
|Age-related macular degeneration||Specific formulation of antioxidant vitamins, zinc and copper|
|Restricted or suboptimal eating patterns||Multivitamin/multimineral, vitamin B12, calcium, vitamin D and magnesium|
|Long-term proton pump inhibitor use||Vitamin B12, calcium and magnesium|
|Long-term metformin use||Vitamin B12|
Read the full study here