Elderly lacto-ovo-vegetarians and vegans often have very low serum B12 levels. They should make sure they are getting a reliable source of B12. In fact, all people over age 50 should get some B12 by way of fortified foods or supplements due to lower stomach acid decreasing absorption of food-bound B12.
Studies of the B12 Status of Elderly Vegetarians
|Table 1. B12 Status of Elderly Lacto-Ovo Vegetarians vs. Non Vegetarians|
|#||Serum B12 (pg/ml)||B12 < 186.3 pg/ml|
|Non-Veg Males||54||Not Reported||4%|
|Non-Veg Females||54||Not Reported||6%|
|Lacto-Ovo Males||17||317 ± 277||35%|
|Lacto-Ovo Females||23||247 ± 96||13%|
They concluded that a lacto-ovo or lacto-vegetarian diet can be adequate in old age, with positive impacts on heart disease risks, provided that it is carefully planned, especially with respect to iron, zinc, and B12.
Woo et al. (1998, Hong Kong) (3) compared 106 elderly Chinese lacto-ovo and vegan women to 229 non-vegetarians:
- All were older than 65 yrs (avg. 81); all were apparently healthy.
- Vegetarians had been on the diet > 10 yrs.
- Low B12 (< 203 pg/ml) occurred in 53.8% of the vegetarians (data not given for non-vegetarians).
- 16 vegetarians had B12-deficient anemia compared to 1 non-vegetarian.
- Vegetarians had a lower prevalence of a history of smoking and heart disease.
There is evidence that adults 65 years and older should take at least 500 µg per day of vitamin B12 in order to optimize their B12 status—see Explanation of Vitamin B12 Recommendations: Adults Over 65 Years. However, there is also evidence—see the paragraph below—that older people might not need so much vitamin B12, and that is why we modified our recommendations to say that supplementation of 50 to 100 µg per day or 1,000 µg at least twice per week should be sufficient for older adults with normal B12 status.
Among a sample of 728 adults within the Adventist Health Study 2, Damayanti et al. (2018, United States) (4) found that younger adults (ages 40 to 49 years) were more likely to have lower markers of vitamin B12 than older adults (ages 70 to 94 years). Nearly 10% of the sample was vegan and 28% were lacto-ovo vegetarian. Males and those not taking vitamin B12 supplements had lower markers of vitamin B12. Older adults were more likely to supplement and supplementation was positively correlated with healthy B12 markers. Next to supplements, fortified plant-based milk alternatives were an important source of vitamin B12 in this sample.
2. Lowik MR, Schrijver J, Odink J, van den Berg H, Wedel M. Long-term effects of a vegetarian diet on the nutritional status of elderly people Dutch Nutrition Surveillance System). J Am Coll Nutr. 1990 Dec;9(6):600-9.
4. Damayanti D, Jaceldo-Siegl K, Beeson WL, Fraser G, Oda K, Haddad EH. Foods and Supplements Associated with Vitamin B12 Biomarkers among Vegetarian and Non-Vegetarian Participants of the Adventist Health Study-2 (AHS-2) Calibration Study. Nutrients. 2018;10(6):722.