Sight is one of the five senses and a crucial part of how most people perceive the world
Great value is attached to good eyesight and healthy eyes. Vision loss becomes more common when people age, but it is important for younger people not to lose sight of the fact that lifestyle choices now can impact their eyes in the future.
In many areas of the world, countries are experiencing a significant increase in the number of elderly citizens. Along with this rise in the proportion of older people, we also see a steady rise in the development of various age-associated chronic diseases, including diseases of the eye.
Refractive errors are the most common cause of impaired vision but can be corrected with prescription lenses. According to the World Health Organization (WHO), vision loss and blindness affect 285 million people or ~4% of the world’s population. The annual economic burden of vision loss and eye disease is substantial; in the United States alone, costs are estimated to be $139 billion.
There are four major age-associated eye diseases: cataract, diabetic retinopathy, glaucoma, and age-related macular degeneration. According to the National Eye Institute at NIH, the relative distribution of eye disease burden in the United States is cataract = 24 million people, diabetic retinopathy = 7.7 million people, glaucoma = 2.7 million people, and age-related macular degeneration = 2.1 million people; in addition, there are 5 million people who suffer with dry eyes.
According to a recent United Nations estimate (Figure 1), the number of people 65 and older is projected to triple by mid-century, from 531 million in 2010 to 1.5 billion in 2050. In the US, the senior population is expected to slightly more than double, from 41 to 86 million. Thus, it can be expected that with the substantial rise in the number of elderly people, the number of people with eye diseases will likewise increase in the United States and worldwide.
Figure 1: Estimated future population change in the United States and the world
With the global population ageing, consumers are all eyes for products that support vision. Demand for eye health products depend on consumers’ age and household situation. Older adults are most likely to be affected by deteriorating vision and have strong personal motivations to maintain normal vision.
An international survey found that around half of consumers cite eye health as a key health concern, and was the second in importance after bone health. Parents are also interested in products that will contribute to their children’s normal visual development. As ageing is a strong driver, the current market is in a growth stage with a CAGR of 6% projected until the end of the decade.
Consumer desire for self-care and preventive action are boons for the eye health market. Products that allow people to manage or avoid eye-related conditions appeal to many. Fortunately for the eye health market, there is also plenty of scientific evidence that supports key ingredients.
For example, compelling evidence shows that supplementation with lutein and zeaxanthin leads to significant increases in the amount of macular pigment in the retina, while an adequate vitamin A status is essential for normal vision. Condition-specific supplements appear to do better than products supporting eye health in general.
Lutein and zeaxanthin: Lutein and zeaxanthin are often considered together as they are the two dietary carotenoids that are found in high concentrations in the eye, particularly in the macula, but also in other parts of the retina and the lens. Lutein and zeaxanthin have various effects on the antioxidant potential of the macula, and also reduce the diffusion of oxygen across membranes in the eye. Lutein and zeaxanthin are thought to have different effects on vision due to their position in the macula.
Lutein concentrates itself in the outer area of the macula where it may reduce glare and assists sight in low-light conditions, while zeaxanthin is found in the center of the macula, where it may protect central vision and enhance contrast sensitivity. Carotenoid-rich diets supply lutein and zeaxanthin in a ratio of 5:1 , which is often reflected in product formulations that supply both ingredients.
Beta-carotene: Beta-carotene is best known for its pro-vitamin A properties. As it is found in high levels in carrots, it gives a factual basis to the concept that carrots are good for vision.
Astaxanthin: Astaxanthin’s potential role in eye health comes from its potent antioxidant activity. In vitro testing has found that it has a 10-fold greater antioxidant activity than other carotenoids such as lutein and beta-carotene.
Vitamins A and C: Both vitamins A and B2 are essential for normal vision. Vitamin A has been long known as a critical nutrient for proper vision and eye health. In addition, the body maintains high levels of vitamin C in both the aqueous humor and the lens, where it scavenges free radicals and regenerates vitamin E and glutathione.
Good nutrition for eye health requires more than high intakes of a few selected ingredients. Nutrients work together to support healthy vision. For example, vitamin C, vitamin E and EPA+DHA in concert support the normal antioxidant functions in the eyes.
A premix is a blend of multiple nutrients carefully formulated to suit the stability, taste, and textural requirements of the end consumer product. Premixes can be a useful means of de-complexing manufacturing of the final product by starting with a carefully controlled blend of the active ingredients fully tested to guarantee potency.
There are some basic factors to consider when formulating and manufacturing a nutrient premix to ensure that the premix meets the requirements of the end application, is stable over the desired shelf-life, and can be produced as a homogenous blend.