UGA Aging-related Research
UGA researcher Dr. Lisa Renzi Hammond begins the slide presentation about her recent research project with pictures of actress Betty White as a beautiful young woman, middle-aged, and at 93, still vibrant.
A second slide of actor Marlon Brando shows him as the hunk he was when young, then as the attractive cinematic Godfather in late middle age, and how he looked before he died at age 80: obese, diabetic, and in heart and liver failure.
Each slide headline reads, “The many ways one can age.”
But it was Paul Newman, at age 82, who inspired Hammond’s research into improving brain health, or cognition. She saw him on a talk show in 2007 explaining his retirement due to loss of memory, confidence and ability to invent. Hammond, clinical assistant professor in the UGA Behavioral and Brain Sciences Program, has done much of her research on the human retina, which is actually a small piece of brain tissue. She’s also part of a relatively new field called nutritional neuroscience, which studies nutrition, diet, and the nervous system.
It’s been known for some time that lutein, a carotenoid found in leafy vegetables, improves eyesight; the macular pigment in the retina is made of lutein and zeaxanthin. While Americans average .3 mg of lutein in their macular pigment, it can range in individuals from none to greater than 1 mg in a standard measure of pigment. The American diet is such that the average lutein intake is 1.5 mg daily.
Supplements containing about 2 mg of lutein have been on drugstore shelves for some time, touting the benefits to eyesight. In fact, some studies have shown lutein can slow macular degeneration, which is the leading cause of severe vision loss in those over age 60. Further, other studies also have shown a strong correlation between macular degeneration and Alzheimer’s disease.
All of these earlier studies on lutein and Paul Newman’s lament about cognitive loss came together so that Hammond wondered if more lutein could improve not just eye health but brain health as well.
The only way to find out was to conduct a randomized, double-blind study, giving half the participants a daily dose of 12 mg of lutein and half a placebo, with no one, researchers included, knowing who was taking which pill. Abbott Nutrition, makers of Ensure, a nutritional supplement, funded the study, which included 24 researchers and assistants from three other universities. Hammond was the principal investigator in the study, which began in 2012.
Athens resident and retired teacher, Iva King, age 67 at the time, was one of 102 adults to take part in the study.
“My memory doesn’t seem as good as it used to be, so I wanted to learn what I could about what is happening,” King says. Half of the participants were between ages 18 and 30, and half were age 65 plus. The testing was extensive, taking about 30 hours per individual over the year. While the study included such typical health testing as blood draws, eye and hearing exams, memory tests, word and shape recognition, other aspects measured the ability to complete tasks such as addressing, stamping, and mailing a letter or reading the directions on a microwave, and heating food, all the while hooked up to an EEG machine that measured brain waves.
Baseline measurement was followed by 4, 8, and 12month testing. Every two weeks, graduate assistants called participants to check on health status and continued use of the daily supplement.
King’s husband Larry also participated in a limited way. The researchers wanted to question someone who knew each person well enough to know their functional skills and who would have been with that person on a recent experience. A golf trip with several couples over a few days was the King’s shared endeavor. Iva remembered everyone’s name but that of one couple; Larry, questioned separately, forgot the same couple!
When the study ended last October, Hammond and her team went over the results of the testing with each participant. While all the data have yet to be analyzed, preliminary results show improved reasoning in both the younger and the older participants. By eight months, older adult participants taking the active supplement improved in complex attention by about 30 percent, in cognitive flexibility by 33 percent and executive function by 24 percent, compared to those taking the placebo.
At the end of the study, all of the participants were given a year’s worth of lutein, and Hammond plans to do followup testing at six months and a year.
Hammond is excited about the lutein results, and nutrition’s effect on cognition, in general, and what it might mean for the future.
“It’s a lifespan story,” she says. Knowing more with these types of studies, “we could build the best brain from day one with nutritional interventions.” In the meantime, she speculates that perhaps the level of lutein in the eye will turn out to be a marker for the rest of the health of the brain; perhaps optometrists will be taught to include a measurement of lutein as part of annual eye exams.
Iva King had a high level of lutein at baseline measurement and since her test scores didn’t change much, she thinks she was taking the placebo. Now, however, she takes 12 mg of lutein daily.
Editor’s note: Hammond says lutein has been tested in mega doses by the FDA and found generally safe. Retailers are stocking lutein in 6 mg and 20 mg doses. However, a cup of cooked spinach or other cooked greens has about 12 mg in it also.
- UGA: Billy Hammond, L. Stephen Miller, Brett Clementz
- Macular Metrics: Billy Wooten
- UNH: Joanne Curran-Celentano
- UIUC: Charles HillmanSUNY Oneonta: Emily Bovier
- Graduate Students – S. Anna Thorne, William Oliver, Cutter Lindbergh, Douglas Terry, Catherine Mewborn, Kevin O’Brien, Laura Fletcher
- Current Laboratory Employees and Research Assistants – Medina Bello, Samy Gabriel, David Cromer, Dahyun Ji, Kodiak Sauer, Jason Champ, Craig Brown, Rebekah Snow, Frances Kittle, Stephen White
- Abbott Nutrition (financial support)
- DSM (nutritional supplements)