A 70-year-old should aim for 2.4 micrograms (mcg) of vitamin B12 per day, as recommended by the National Institutes of Health (8).
Ideally, this should come from a balanced diet; foods such as fish, poultry, eggs, and fortified cereals are excellent sources of B12. However, if a senior is unable to meet their daily needs through diet alone, they may consider taking a B12 supplement after consulting a healthcare professional.