There’s no such thing as a quick fix—or is there?

I’ve spent much of the last five years researching vitamins and supplements that maximize cognitive ability. In brief, here’s what I know: In order to keep your marbles, you need plenty of antioxidants, essential fatty acids, B vitamins and magnesium in your diet. Unless you’re a grazing animal, it’s highly unlikely that you can obtain all the antioxidants you need exclusively from the food you eat. (You’d have to gobble fruits and veggies all day long, which can get messy in the car.) After you swallow as many antioxidants as you can (and don’t forget spices like curcumin—the yellow pigment found in turmeric—and cinnamon), you can supplement with coenzyme Q-10. It’s one of the few antioxidants that’s fat soluble, which means that it can rapidly cross the cell membrane, the better to protect you against free radicals.

About 40 percent of midlife Americans are deficient in essential fatty acids, also known as Omega-3s, which are critical for optimal neuronal function. EFAs comprise the raw material of myelin, the covering of lipid fat that surrounds a neuron’s delicate branches. They also form the cell membrane, which maintains a neuron’s structural integrity. EFAs make the membrane more fluid and flexible, allowing the cell to be more receptive to incoming signals. Top sources of EFAs are fatty coldwater fish like wild salmon, but you can also get EFAs from almonds, pecans, soybeans, walnuts, flaxseeds and avocado. Because of the danger of mercury toxicity, you can’t eat sufficient cold-water fish to satisfy your EFA requirement, but you can bolster your diet with supplements and get what you need: EFAs are available in mercury-safe “Omega-3” fish oil capsules.

Check your multivitamin to make sure that there are plenty of B-vitamins on board (and don’t expect to find enough in a cheap supermarket brand). Put your vitamin through the folate test—if the label lists 400 micrograms of folate, it’s likely to be a good one. B vitamins are required for the conversion of glucose to energy—and glucose is what fuels your brain.

Magnesium is the mineral du jour when it comes to maintaining your midlife cognitive chops. Up to 80 percent of people in the United States are magnesium deficient, a condition that may result in a short attention span, confusion, memory loss, insomnia, mood changes, apathy and fatigue. Sound familiar? Unless you’re a serious fan of Brussels sprouts and kale, there’s practically no magnesium in the food we eat. Research emerging from MIT shows that 420 milligrams of magnesium for males, and 320 milligrams for females helps maintain the plasticity of nerve cells, as well as several levels of neurotransmitters. Taking calcium and magnesium helps both supplements work better—and may contribute to sounder sleep.

Yesterday, I was paging through Science News, one of the scientific journals I read every week, and I found something that sent me scuttling to the Whole Foods vitamin and supplement aisle. It was an article about Rhodiola rosea, a sweet-smelling mountain herb that has been studied for decades in Russia. I'd heard about it before, but I'd put it on a long list of untested herbs of questionable value. (Virtually all studies that come out of the former USSR find whatever treatment is being tested to be effective. In the case of rhodiola, the details of research remained locked away because the herb was considered a top military secret.) Here, on the page, were the results of several high-quality clinical trials, in Sweden and the U.K., in conjunction with Russian investigations.

Apparently, the root of this yellow, flowering plant—one of a family of plants known as adaptogens—can do some remarkable things. Laboratory and animal studies show that the herb may inhibit cancer cells, protect healthy cells from toxins, and correct enzyme imbalances associated with diabetes. In animals, rhodiola lowers the stress hormone known as cortisol, and acts as an antioxidant. In addition, four trials with human volunteers show that rhodiola extracts can boost mental performance, prevent altitude sickness and reduce fatigue. It has been used successfully to alleviate depression. And it seems to help people who are suffering from the neurocognitive side affects of Lyme disease. In Russia, athletes and cosmonauts use it because it appears to increase aerobic capacity, speeds recovery of the circulatory system, and allows them to function under conditions of sleep deprivation, while maintaining their cognitive capacity.

How does it work? Russian studies suggest rhodiola optimizes serotonin and dopamine levels, and stimulates production of endorphins, but that’s obviously just the tip of the iceberg—more research is needed. If the herb can alleviate depression and improve mental functioning, it would be valuable indeed. Typically, antidepressants, which are strongly sedating, make patients a little foggier than they’d normally be.

A typical dosage is two 100-milligram capsules, taken in the morning. Taken too late in the day, rhodiola might interfere with sleep. There are no known safety issues with rhodiola, but comprehensive studies have not been performed. Check with your physician before taking it or any other vitamin or supplement, especially if you are taking other medications, including antidepressants. The response to this herb is very rapid—some people report improved mental states in a matter of days.

I’m swallowing my capsules right now. Give me a few weeks, and I’ll let you know. I’m not depressed. But it would be nice to feel a little sunnier as winter sets in. Hope springs eternal—maybe there is a quick fix after all.

For more on the subject of brain nutrition, take a look at “Swallow This,” Chapter Six of Carved In Sand: When Attention Fails and Memory Fades in Midlife.

"Is what I'm experiencing ordinary midlife forgetfulness? Or do these memory lapses signify something more serious—like the first signs of Alzheimer's disease?"

Practically every day, someone asks me these questions. And I wish I had better answers. One evening, a white-haired gentleman rose to his feet in a jam-packed auditorium. Anxiously, he asked me to confirm that forgetfulness was a perfectly normal part of aging, without pathological implications.

That, to my sorrow, I could not do. Reluctantly, I told him what I knew. Every day, a new study rolls out of a university lab confirming that Alzheimer's isn't a disease that suddenly rears its head in old age. Current research shows that decades before clinical symptoms arise—in middle age or even before—the seeds of Alzheimer's are already planted. To insist otherwise is to indulge in the most unhealthy sort of denial.

Like the rest of our bodies, our brains change as we get older. Proteins that were once smoothly soluble begin to aggregate, impeding communication between neurons, resulting in mild forgetfulness. For many of us, that's where it stops. But in others, those same tiny proteins get out of control, triggering the development of dense plaques and tangles that surround neurons, infiltrate them and eventually strangle them. Today's scientists are working hard to develop a test that will show—at the earliest possible moment—who’s taking the wrong fork in the road.

The goal of nearly every Alzheimer's researcher is to find a way to identify the beginning of the disease process. "If we can meet this disease in the earliest stage and counteract it with drugs that reverse the damage, science would no longer be in the position of needing to build new neurons," says John Q. Trojanowski, director of the Penn Institute on Aging and Alzheimer's Disease at the University of Pennsylvania. "It is in your forties, or maybe even younger, that normal memory loss begins to diverge from pathological memory loss. In my lab, we’re spending a lot of time trying to define that fork in the road, where you either continue to lose a little bit of your memory capacity each year, and remain essentially normal, or you take the other fork, where you are on a downward trajectory, culminating in dementia."

Trojanowski's lab at Penn is on the leading edge of the hunt for a biological marker—the equivalent of a pregnancy test—for Alzheimer’s disease. This "biomarker" must be fast, painless, inexpensive and able to pick up indicators of the disease at a very early stage, permitting early diagnosis, before neurons begin to die. In order to know whom to treat, it's essential to know who is vulnerable. As part of a National Institute of Aging investigation, the Alzheimer's Disease Neuroimaging Initiative, or ADNI, Trojanowski’s lab has made significant progress in tracking down a marker for the elevated presence of tau and amyloid beta proteins in cerebrospinal fluid. It's accurate, and meets most of the criteria, but is of limited use in a once-a-year doctor's check up, since not many of us would like to top off our annual physicals with a spinal tap.

That's why people got so excited earlier this week when scientists at Stanford University announced that they had developed a blood test that can diagnose Alzheimer's disease years before memory loss is evident. The test shows a 90 percent accuracy rate in its ability to predict who would develop Alzheimer's disease two to six years in the future, by measuring eighteen proteins involved in cell signaling. The proteins that neurologist Tony Wyss-Coray assessed were not even on the list of "promising" blood chemicals identified in 2003 by the National Institute on Aging study—but often, that's how science works. For years, researchers pursue a hypothesis, adding bit by bit to existing knowledge—only to have another team of researcher turn that hypothesis on its ear and shout "Eureka, we’ve found it!"

The Stanford blood test, promising as it is, requires more extensive testing, in a larger sample of patients and control subjects, including confirmation of accuracy that can emerge only after the autopsies of deceased study participants. It will take several years to do these studies, and in the meantime, given the intense focus on this effort, other biomarkers in blood and urine are likely to emerge. That's good news for all of us. Within a few years, when you go to see your primary care practitioner, there will be one more box checked on the sheet you take to the blood lab—one that will tell your physician what’s going on in your brain. "It goes painful step by painful step," John Trojanowski emailed me, when I asked him what he thought of the Stanford news, "but this is progress that takes us closer to meaningful therapies."

For more on biomarkers, go to Carved in Sand Chapter 1, Your Unreliable Brain, and Chapter 18, Do You Really Want to Know.