Nav: Home

Vitamin A orange maize improves night vision

October 24, 2016

Washington D.C., Oct. 24, 2016--A new study has found that vitamin A-biofortified orange maize significantly improves visual functions in children.

The study was conducted among school-aged children (4 to 8 years old) in rural Zambia. Children who ate orange maize showed improved night vision within six months. Their eyes adapted better in the dark, improving their ability to engage in optimal day-to-day activities under dim light, such as during dusk and dawn. The study was published in The Journal of Nutrition.

"It shows that in populations that are vitamin A deficient, the eyes can respond well to a good source of vitamin A such as orange maize in a fairly short span of time," says lead author Amanda Palmer of Johns Hopkins Bloomberg School of Public Health. "It also validates the importance of orange maize for tackling vitamin A deficiency as part of a food-based approach."

Vitamin A deficiency occurs on a continuum. Severe vitamin A deficiency with blinding eye disease and a high risk of death from otherwise curable infections is at one end of the spectrum. But, less severe, incipient vitamin A deficiency -- also an important underlying cause of child deaths--is more frequent and difficult to detect. According to the World Health Organization, lack of sufficient vitamin A blinds up to 500,000 children worldwide every year.

Impairment of the eyes' ability to adapt to low-light conditions is one of the few measurable signs of vitamin A deficiency at its initial stages. In this study scientists used specialized portable equipment to confirm the benefit of eating vitamin A-rich orange maize in a population with marginal deficiency.

"It is an impressive advancement that with portable, more user-friendly equipment scientists are now able to accurately record the changing size of the pupils of the children's eyes," says Erick Boy, Head of Nutrition at HarvestPlus and a pediatrician by training. "In this study, the researchers documented how children's eyes responded to different light conditions before and after a six-month feeding period. This used to be a much more cumbersome task until now."

Testing for vitamin A deficiency is problematic because blood collection can prove difficult in rural settings. Levels of vitamin A in the blood may also be affected by other factors, such as infections. Rapid, reliable and non-invasive tools to measure the positive impact of nutritional interventions on the vision of those suffering from marginal deficiency were practically unavailable before this study.

Scientists in this study used a new device called a Portable Field Dark Adaptometer (PFDA). The PFDA is a set of goggles manufactured with a digital camera and flash inside. The goggles are connected to a desktop or laptop computer, which can accurately record the response of the pupil in each eye to changing light conditions.

The Johns Hopkins team is the first to use this device on a large scale.

"Until now, most of the tools and techniques used to measure night vision have relied on dark rooms, which are impractical in rural field settings. And, results were subjective," says Palmer. "With PFDA we don't need a tent or a dark room and it gives accurate results for people aged 3-4 years or older." This randomized efficacy study was conducted in Zambia's Mkushi District among children who were marginally vitamin A deficient. They were served two meals per day, six days a week for six months. Half of the children got meals made from biofortified orange maize, while the other half consumed white maize meals.

The children wore PFDA goggles to record pupil response. "We measured the responsiveness of the pupil to light and calculated the change in pupil size over a period of time. These goggles enabled us to monitor something that was not possible before," says Palmer.

The biofortified orange maize used in this study was conventionally bred to have higher levels of beta-carotene, a naturally occurring plant pigment that the body converts into vitamin A with higher efficiency as the body stores of the vitamin decrease.
-end-
More about orange maize in Zambia

The Zambian Government is actively promoting vitamin A-rich orange maize developed by HarvestPlus and its partners through conventional plant breeding methods. Maize is a staple food in Zambia and its enrichment can help combat the rampant problem of vitamin A deficiency, whose ill effects can include stunted growth and blindness. Zambia has banned the export of orange maize so that nutritious maize stays in the country to nourish its own people. The country's Ministry of Agriculture and Livestock has included orange maize seeds as one of the material supplies that can be procured under the Farmer Input Support Programme (FISP). The ministry is urging farmers, millers, and seed companies to become ambassadors and advocates of biofortified nutritious maize. This message is reaching Zambians. The adoption rate for orange maize is fairly high in Zambia, and HarvestPlus expects that at least 600,000 households will have adopted the crop by 2020.

More about orange maize in Zimbabwe

Zimbabwe has become the latest African country to move toward making biofortified nutritious crops widely available to farmers and consumers. On August 18, 2016, the Zimbabwean Government officially launched widespread distribution and marketing of biofortified crop seeds under a project implemented by the United Nations Food and Agriculture Organization (FAO). HarvestPlus is a strategic partner and technical advisor to the project.

Two biofortified crops -- vitamin A orange maize, and iron and zinc beans -- have already been released, with seeds expected to be available across the country in readiness for the 2016/2017 planting season. Farmers in the country can now access one variety of the orange maize and two of the iron and zinc beans, but will soon have more to choose from when varieties already in the pipeline are released.

Press Release Journal Article http://jn.nutrition.org/content/early/2016/10/19/jn.116.239202.full.pdf

Made available as free open access

More About HarvestPlus

HarvestPlus improves nutrition and public health by developing and promoting biofortified food crops that are rich in vitamins and minerals, and providing global leadership on biofortification evidence and technology. HarvestPlus is part of the CGIAR Research Program on Agriculture for Nutrition and Health (A4NH). CGIAR is a global agriculture research partnership for a food secure future. Its science is carried out by its 15 research centers in collaboration with hundreds of partner organizations. The HarvestPlus program is coordinated by two of these centers, the International Center for Tropical Agriculture (CIAT) and the International Food Policy Research Institute (IFPRI).

HarvestPlus

Related Public Health Articles:

Pandemic likely to cause long-term health problems, Yale School of Public Health finds
The coronavirus pandemic's life-altering effects are likely to result in lasting physical and mental health consequences for many people--particularly those from vulnerable populations--a new study led by the Yale School of Public Health finds.
The Lancet Public Health: US modelling study estimates impact of school closures for COVID-19 on US health-care workforce and associated mortality
US policymakers considering physical distancing measures to slow the spread of COVID-19 face a difficult trade-off between closing schools to reduce transmission and new cases, and potential health-care worker absenteeism due to additional childcare needs that could ultimately increase mortality from COVID-19, according to new modelling research published in The Lancet Public Health journal.
The Lancet Public Health: Access to identification documents reflecting gender identity may improve trans mental health
Results from a survey of over 20,000 American trans adults suggest that having access to identification documents which reflect their identified gender helps to improve their mental health and may reduce suicidal thoughts, according to a study published in The Lancet Public Health journal.
The Lancet Public Health: Study estimates mental health impact of welfare reform, Universal Credit, in Great Britain
The 2013 Universal Credit welfare reform appears to have led to an increase in the prevalence of psychological distress among unemployed recipients, according to a nationally representative study following more than 52,000 working-age individuals from England, Wales, and Scotland over nine years between 2009-2018, published as part of an issue of The Lancet Public Health journal on income and health.
BU researchers: Pornography is not a 'public health crisis'
Researchers from the Boston University School of Public Health (BUSPH) have written an editorial in the American Journal of Public Health special February issue arguing against the claim that pornography is a public health crisis, and explaining why such a claim actually endangers the health of the public.
The Lancet Public Health: Ageism linked to poorer health in older people in England
Ageism may be linked with poorer health in older people in England, according to an observational study of over 7,500 people aged over 50 published in The Lancet Public Health journal.
Study: Public transportation use linked to better public health
Promoting robust public transportation systems may come with a bonus for public health -- lower obesity rates.
Bloomberg American Health Initiative releases special public health reports supplement
With US life expectancy now on the decline for two consecutive years, the Bloomberg American Health Initiative is releasing a supplement to Public Health Reports, the scholarly journal of the US Surgeon General.
Data does the heavy lifting: Encouraging new public health approaches to promote the health benefits of muscle-strengthening exercise (MSE)
According to a new study in the American Journal of Preventive Medicine, almost 75 percent of US adults do not comply with public health guidelines recommending two or more muscle-strengthening exercise (MSE) sessions a week, with nearly 60 percent of the population doing no MSE at all.
The Lancet Public Health: Moderate carbohydrate intake may be best for health
Low-carb diets that replace carbohydrates with proteins and fats from plant sources associated with lower risk of mortality compared to those that replace carbohydrates with proteins and fat from animal sources.
More Public Health News and Public Health Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Making Amends
What makes a true apology? What does it mean to make amends for past mistakes? This hour, TED speakers explore how repairing the wrongs of the past is the first step toward healing for the future. Guests include historian and preservationist Brent Leggs, law professor Martha Minow, librarian Dawn Wacek, and playwright V (formerly Eve Ensler).
Now Playing: Science for the People

#565 The Great Wide Indoors
We're all spending a bit more time indoors this summer than we probably figured. But did you ever stop to think about why the places we live and work as designed the way they are? And how they could be designed better? We're talking with Emily Anthes about her new book "The Great Indoors: The Surprising Science of how Buildings Shape our Behavior, Health and Happiness".
Now Playing: Radiolab

The Third. A TED Talk.
Jad gives a TED talk about his life as a journalist and how Radiolab has evolved over the years. Here's how TED described it:How do you end a story? Host of Radiolab Jad Abumrad tells how his search for an answer led him home to the mountains of Tennessee, where he met an unexpected teacher: Dolly Parton.Jad Nicholas Abumrad is a Lebanese-American radio host, composer and producer. He is the founder of the syndicated public radio program Radiolab, which is broadcast on over 600 radio stations nationwide and is downloaded more than 120 million times a year as a podcast. He also created More Perfect, a podcast that tells the stories behind the Supreme Court's most famous decisions. And most recently, Dolly Parton's America, a nine-episode podcast exploring the life and times of the iconic country music star. Abumrad has received three Peabody Awards and was named a MacArthur Fellow in 2011.