Do you have trouble remembering names and phone numbers? How about where you put things? Do you sometimes struggle to come up with the right word?

Mild forgetfulness, known as age-related memory impairment, is a natural part of getting older. By age 75, a person’s memory has declined, on average, by about 43%. After age 75, the ­hippocampus, the part of the brain most closely associated with memory, will eventually atrophy at the rate of 1% to 2% each year.

But you can improve memory with over-the-counter supplements—if you choose the right ones. Here are the supplements I find most effective with my patients. You can take several of these if you choose. You could start with phosphatidylserine and add others depending on your personal needs. For example, if you’re taking a medication that depletes CoQ10, you might want to take that supplement. Or if you’re under stress, add ashwagandha root. Of course, always check with your doctor before starting any new supplement. To find a practitioner trained in this field, go to Metabolic-Anti-AgingSpecialist.com.

Phosphatidylserine (PS). Most people haven’t heard of it, but PS is one of my first choices for mild memory loss. It’s a naturally occurring phospholipid (a molecule that contains two fatty acids) that increases the body’s production of ­acetylcholine and other neurotransmitters. It improves cell-to-cell communication and “nourishes” the brain by improving glucose metabolism.

Studies have shown that healthy people who take PS are more likely to maintain their ability to remember things. For those who have already ­experienced age-related memory loss, PS can improve memory. It’s also thought to improve symptoms caused by some forms of dementia.

Typical dose: 300 mg daily. You’re unlikely to notice any side effects.

Co-enzyme Q10 (CoQ10). This is another naturally occurring substance found in many foods (such as fatty fish, meats, nuts, fruits and vegetables) and in nearly all of your body’s tissues. CoQ10 increases the production of ­adenosine triphosphate, a molecule that enhances energy production within cells. It’s also a potent antioxidant that reduces cell-damaging inflammation in the brain and other parts of the body.

People with degenerative brain disorders, such as Alzheimer’s, tend to have lower levels of CoQ10. Studies suggest that supplemental CoQ10 improves memory by protecting brain cells from oxidative damage.

Important: If you’re taking a medication that depletes CoQ10—examples include statins (for lowering cholesterol)…metformin (for diabetes)…and ­beta-blockers (for heart disease and other conditions)—you’ll definitely want to take a supplement. I often recommend it for people age 50 and older because the body’s production of CoQ10 declines with age. Hard exercise also depletes it.

Typical dose: Between 30 mg and 360 mg daily. Ask your health-care professional how much you need—it will depend on medication use and other factors. Side effects are rare but may include insomnia, agitation and digestive problems such as diarrhea and heartburn.

Acetyl-L-carnitine. A study that looked at people with mild cognitive impairment (an intermediate stage between age-related memory impairment and dementia) found that acetyl-L-carnitine improved memory, attention and even verbal fluency.

Acetyl-L-carnitine (it is derived from an amino acid) is a versatile molecule. It’s used by the body to produce acetylcholine, the main ­neurotransmitter involved in memory. It slows the rate of neurotransmitter decay, increases oxygen availability and helps convert body fat into energy.

Typical dose: 1,000 mg to 2,000 mg daily. Check with your health-care professional before starting acetyl-L-­carnitine to see what dose is best for you. If your kidneys are not functioning perfectly, you may need a lower dose. Some people may notice a slight fishy body odor. In my experience, you can prevent this by taking 50 mg to 100 mg of vitamin B-2 at the same time you take acetyl-L-carnitine.

Ashwagandha root. This is an herb that improves the repair and regeneration of brain cells (neurons) and inhibits the body’s production of acetylcholinesterase, an enzyme that degrades acetylcholine. It also improves the ability to deal with both physical and emotional stress—both of which have been linked to impaired memory and cognitive decline.

Typical dose: 500 mg to 2,000 mg daily. Start with the lower dose. If after a month you don’t notice that your memory and focus have improved, take a little more. GI disturbances are possible but not common.

Warning: Don’t take this supplement if you’re also taking a prescription medication that has cholinesterase-­inhibiting effects, such as donepezil (Aricept) or galantamine (Razadyne). Ask your health-care professional whether any of your medications have this effect.

Ginkgo biloba. Among the most studied herbal supplements, ginkgo is an ­antioxidant that protects the hippocampus from age-related atrophy. It’s a vasodilator that helps prevent blood clots, improves brain circulation and reduces the risk for vascular dementia, a type of dementia associated with impaired blood flow to the brain. It also increases the effects of serotonin, a neurotransmitter that’s involved in mood and learning.

Bonus: In animal studies, ginkgo appears to block the formation of amyloid, the protein that has been linked to Alzheimer’s disease. There’s strong evidence that ginkgo can stabilize and possibly improve memory.

Typical dose: 60 mg to 120 mg daily. Most people won’t have side effects, but ginkgo is a blood thinner that can react with other anticoagulants. If you’re taking warfarin or another blood thinner (including aspirin and fish oil), be sure to check with your health-care professional before taking ginkgo.

Fish oil. Much of the brain consists of DHA (docosahexaenoic acid), one of the main omega-3 fatty acids. It is essential for brain health. People who take fish-oil supplements have improved brain circulation and a faster transmission of nerve signals.

Studies have found that people who eat a lot of fatty fish have a lower risk for mild cognitive impairment than people who tend to eat little or no fatty fish. One study found that people with age-related memory impairment achieved better scores on memory tests when they took daily DHA supplements.

Typical dose: 2,000 mg daily if you’re age 50 or older. Look for a combination supplement that includes equal amounts of DHA and EPA (another omega-3). Fish-oil supplements can increase the effects of blood-thinning medications such as aspirin and warfarin if the dose is above 3,000 mg a day.

Huperzine A. Extracted from a ­Chinese moss, this is a cholinesterase inhibitor that increases brain levels of acetylcholine. It also protects brain cells from too-high levels of glutamate, another neurotransmitter.

Huperzine A may improve memory and could even help delay symptoms of Alzheimer’s disease. A study conducted by the National Institute of Aging found that patients with mild-to-moderate ­Alzheimer’s who took huperzine A had improvements in cognitive functions.

Recommended dose: 400 mcg daily. Don’t take it if you’re already taking a prescription cholinesterase inhibitor (as discussed in the “Ashwagandha root” section).