Beneficial Interactions Between B Vitamins and Omega‐3 Fatty Acids in the Prevention of Brain Atrophy and of Cognitive Decline in Early Stage Alzheimer's Disease

Taking B vitamins might help protect your brain from shrinking, but only if you already have enough omega-3s in your body—like from fish or supplements.

If you're an older adult with mild memory problems, having more DHA (a type of omega-3 found in fish) in your blood might make B vitamins work better to help your brain, and DHA seems to help more than another omega-3 called EPA.

Some scientists think that taking B vitamins and omega-3s together might help slow memory loss in people with early memory problems, because B vitamins help turn one type of fat in the brain into another that’s full of omega-3s and helps brain cells communicate better.

For older people with early memory problems, taking B vitamins for two years might help slow memory loss and delay Alzheimer’s — but only if their blood already has high levels of omega-3 fats. In that group, fewer people on B vitamins got worse compared to those on a placebo.

Taking B vitamins won't help your memory or thinking if you don't already have enough omega-3s in your body — it's like trying to start a car with no gas, even if you turn the key.

Taking B vitamins and omega-3s together might slow down early Alzheimer’s disease, but only if you already have enough omega-3 in your body when you start.