Thanks for the memories

President Ronald Regan is perhaps the world’s most well known Alzheimer’s disease patient. Here’s a man, famous for his vigor and vitality during those years well beyond what we think of as “retirement” age. And yet, sadly, over the past decade, he’s virtually disappeared from public life.

During that decade, the number of Alzheimer’s patients has jumped at such an alarming rate that the Alzheimer’s Association (AA) now predicts that in less than 25 years, as many as 22 million people will be diagnosed with the disease worldwide.

HSI has taken a special interest in Alzheimer’s disease because we believe there are natural ways to help prevent this epidemic from ever reaching those numbers predicted by the AA. In the past I’ve promised to keep you abreast of new developments in the research of Alzheimer’s prevention, and I’ve just found a study that confirms the importance of a specific set of nutrients that every person who’s reached middle age needs to be aware of.

California recall 

As we’ve seen in previous studies, elevated levels of the amino acid homocysteine have been linked with Alzheimer’s disease and other forms of dementia. Considerable research has also demonstrated that foods and supplements rich in vitamins B6, B12, and folic acid help reduce homocysteine levels.

Knowing this, a team of researchers from the University of California (UC) evaluated the relationship of plasma homocysteine concentration and cognitive function of more than 1,700 subjects over the age of 60, all of whom were enrolled in the Sacremento Area Latino Study on Aging. The researchers used a variety of neuropsychological tests specifically designed to study cognitive functions of older people. They also had access to data from blood samples, nutrient intake information, and demographic variables.

After analyzing the cognitive function results against the other data, the UC team found a “modest” association between elevated homocysteine levels and indicators for cognitive decline. They also concluded that the use of B vitamin supplements may provide some protection against cognitive decline among the elderly.

Although these results aren’t what you’d call dramatically significant, when compared with other, more conclusive research, the UC study provides confirmation of the existing evidence that B vitamins do in fact provide a measure of prevention against Alzheimer’s.

Years of study

Longtime HSI members will recall that we revealed the association between Alzheimer’s and elevated homocysteine levels more than a year before it became a hot topic in the mainstream medical journals. In both e-Alerts and Members Alerts we’ve reported the following test results:

  • 1996 – A study of elderly Americans, published in the American Journal of Clinical Nutrition (AJCN), found that those with high homocysteine levels performed poorly on cognitive tests compared with those who had low homocysteine levels. Low levels of vitamin B12 and folic acid were also associated with low cognitive test scores.
  • 1997 – A 6-year study, (also reported in AJCN) found that subjects who supplemented with vitamins B6 and B12 performed better on cognitive tests, including recall ability.
  • 2002 – A study of more than 1,000 participants in the Framingham Heart Study showed that subjects who had elevated homocysteine levels but no cognitive problems in 1992 were more likely to have an onset of dementia eight years later.
There are many more examples, but you get the picture. We continue to see more and more evidence in different types of trials that certain B vitamins are effective in lowering homocysteine levels, and helping to prevent the onset of Alzheimer’s and other forms of age-related dementia.

And of course, any discussion of homocysteine would be incomplete without mentioning that elevated homocysteine levels have also been associated with an increased risk of cardiovascular disease, heart attack, stroke, and Parkinson’s disease.

Strong to the “finich”

When homocysteine is not properly metabolized, levels of the amino acid rise. But nutrients such as vitamins B6, B12, and folate help metabolize homocysteine. These nutrients are found in dietary sources such as asparagus, lentils, chickpeas, most varieties of beans, and especially spinach and other leafy green vegetables. But many people don’t absorb B vitamins well, so in addition to these food sources, a B vitamin supplement is often required to lower homocysteine levels.

And according to several studies, supplements of the antioxidant amino acid N-acetylcysteine (NAC) may also lower homocysteine levels. In 2001 we reported on one study that showed how NAC improved cognitive function in patients with probable Alzheimer’s Disease. The 24-week study of 47 subjects revealed that those participants who took NAC showed improvement in nearly every outcome measure, without experiencing any negative side effects.

Tell a friend 

The next time your doctor takes a blood sample, ask about your homocysteine level and discuss this important issue. (Most doctors consider any level over12 micromoles per liter to be an elevated homocysteine level.) And if you know someone who has concerns about preventing Alzheimer’s and other age-related dementia, please help me on this mission to get the word out.

Share this e-Alert with friends and let them know that lowering homocysteine today could make an important difference in the quality of their lives during the coming years.

To Your Good Health,

Jenny Thompson
Health Sciences Institute

“Homocysteine and cognitive function in the Sacramento Area Latino Study on Aging” American Journal of Clinical Nutrition, Vol. 78, No. 3, 441-447, September 2003,

“Vitamin to Reduce Homocysteine may Help Cognition”, 9/24/03,