New insights on lutein and cognition

Cognition is described as the ability to think, learn and remember. As people age, the brain naturally changes, affecting memory, learning and other cognitive functions. Some older adults suffer from mild cognitive impairment, in which they have more memory or thinking problems than other people their age. Dementia is the loss of cognitive function and behavioral abilities to such an extent that it interferes with daily life. Memory loss, though common, is not the only sign. A person may also have problems with language skills, visual perception or paying attention.

Dementia comes in different forms, although Alzheimer's disease is the most common form in people over the age of 65. Alzheimer’s is a progressive disease beginning with mild memory loss, possibly leading to the inability to carry on a conversation and respond to the environment.

The Centers for Disease Control and Prevention (CDC) considers Alzheimer’s and dementia a growing health epidemic with profound social and economic implications, especially given the current trends of an aging population. The number of older people in the United States with Alzheimer’s is projected to grow to 13.8 million by 2050, a nearly three-fold increase from 4.7 million in 2010.

According to CDC, the number of people living with the disease doubles every five years beyond age 65. Globally, the World Health Organization (WHO) estimates 35.6 million people are currently living with dementia and the number will nearly double every 20 years, reaching 115.4 million worldwide in 2050. By 2040, the costs associated with Alzheimer’s are projected to hover somewhere between US$379 and $500 billion annually.

The Brain Nutrition Market

For many years, the link between cognitive function and nutrition was little understood within the scientific and medical communities. Today, however, scientists understand the importance of nutrition in maintaining optimal cognitive function. We now know vitamins, minerals and antioxidants nourish the brain and protect it from oxidative stress, while diets high in processed or refined foods are harmful to the brain.

Spurred by growing concern over brain health, cognitive nutrition has become an exciting area of growth and is expected to become a US$1 billion category in the next three years.

Among the most established ingredients in this field are omega-3s and magnesium. DHA (docosahexaenoic acid), an omega-3 fat, makes up a significant percentage of fat in the brain and is required for optimal development.

Lutein: An Up-and-Comer in Brain Nutrition

Lutein, already known for its eye health benefits, is also showing promise in the cognitive nutrition sector. New research points to the benefits of lutein beyond eye health, especially since the eye is also considered neural tissue. Because lutein passes the blood-brain barrier, its ability to confer cognitive benefits makes sense.

Retinal tissue is, in effect, an extension of the brain, and lutein levels in the macula are correlated with levels in neurological tissue. Lutein is found in a variety of human tissues and is especially concentrated in the macular region of the retina, where it is believed to protect against harmful blue light, oxidative damage and macular degeneration. Lutein is also a major carotenoid found in the brain.

Lutein has been studied in relation to brain-derived neurotropic factor (BDNF), a critical compound associated with short- and long-term memory as well as learning and higher cognitive processes. BDNF belongs to a family of proteins that play a role in the development and function of neurons. Neurotrophins like BDNF are powerful compounds that can protect brain cells and facilitate the growth of new neurons in certain regions of the brain. BDNF plays an important role in optimizing cognition by allowing the brain to change and adapt over a person’s lifetime and has been a target area for many nutritional ingredients, including lutein.

In a six-month randomized, double-blind, placebo-controlled study by Stringham et. al., subjects were supplemented daily with either a placebo or two different doses of lutein and zeaxanthin isomers (FASEB J. 2016 April;30(1)). Serum BDNF and macular pigment optical density (MPOD—the “thickness” of the layer of carotenoids that cover the macula in the eye) were assessed at baseline and six months. After six months of lutein and zeaxanthin isomers supplementation, both MPOD and serum BDNF increased significantly compared to placebo. Further analysis of the change in MPOD versus the change in BDNF produced a significant positive correlation, indicating the increase in MPOD after supplementing with lutein and zeaxanthin isomers leads to proportional increases in systemic BDNF levels, including the brain.

As the issues surrounding cognitive decline continue to take center stage in many health care and family settings, more investigation into the application of nutrients to prevent these issues before they start will likely be of high interest. Based on recent research, lutein deserves a seat at the table for that conversation alongside nutrients like omega-3s and magnesium.

Brian Appell is marketing manager of OmniActive Health Technologies.