Alfred Sommer
(October 2, 1942 - )
Born in the United States
Year of Discovery: 1982
Discovered that Providing Vitamin A Tablets to Children Saves Lives

Alfred (Al) Sommer discovered that children with vitamin A deficiencies are at a greatly increased risk of death. Children in developing countries are especially at risk. But, for less than five cents per year, Sommer found, these children can be saved.

Sommer made his remarkable finding after studying the impact of vitamin A deficiency in Indonesia. It was well known that vitamin A deficiency caused blindness, so Sommer and his colleagues spent three years performing studies Sommer designed on groups of children, both those who were healthy and those with signs of nutritional blindness. He made some landmark discoveries about the epidemiology of the disease, and an effective treatment.

Sommer had a restless mind, so even after finishing his analysis, he periodically re-examined his studies. During one such re-analysis, during Christmas break in Baltimore, he suddenly realized that children were dropping out of the discovery.  The expected reason was that their parents were no longer bringing them in. But he suddenly realized there might be another possibility - they were dropping out because they were dying!  More investigation proved this true, which was new to science.  Vitamin A deficiency did not just cause blindness in children - it also caused death! It was a major medical breakthrough, with significant consequences for the entire world's population.

 Not only did Sommer discover the deadly effects of vitamin A deficiency, he also developed the most effective and economical treatment. At the time, vitamin A injections were used to treat any deficiency. The vitamin A he was provided for the study did not work well as an injection and it would take months for the manufacturer to develop a properly constituted injection. So Sommer innovated. He began squirting vitamin A into children's mouths. It worked wonderfully well and he backed up his success with a study.

Initially, neither Sommer's findings about oral doses or the increased mortality of children with vitamin A deficiency were well received by the medical community. Some thought the fix was too simple to prevent such a devastating pattern of deaths. Others thought the reduction in mortality was too large to be true. So Sommer set about performing new studies in the Philippines, Nepal, India, Ghana - essentially, all over the world. In the end, Sommer's evidence was overwhelming. The world's health professionals became convinced, and his treatment methods became the standard.
 

Written by science writer, Tim Anderson

Lives Saved:  Over 23,000,000

Read Sommer's Feature Chapter in the Book

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Snippets
Take a Vacation - Please!
Sommer's first position after Harvard Medical School was in the Epidemic Intelligence Service, a division of the CDC. He threw himself into his work and soon began generating numerous proposals for new initiatives he believed the center should pursue. All this activity made his colleagues and superiors nervous, so one day his boss cornered him. "Al," he said, "we have all voted for you to go home for two weeks and relax." Shortly after he returned, he was on his way to East Pakistan to study cholera.

Action Over Academics Anytime...
Sommer was invited to join the faculty at Johns Hopkins when he graduated, but he was not the conservative, academic-tenure track type of doctor. He told them of the opportunity to do research in Indonesia. Colleagues warned him that he would lose his place on the faculty and would be forgotten, but Sommer told them, "No, I have this wonderful opportunity to go overseas, work with people in another culture. I have something to contribute and it is intrinsically a very interesting series of questions that need to be answered."

Are You Talking To Me?
The research Sommer completed became quite personal. Indonesia is a country with over 300 languages. Both he and his wife learned to speak Malay, the Austronesian language spoken throughout Indonesia, Malaysia, Singapore, Brunei and Thailand.

Mother Knows Best
Sommer found that sometimes science is simply no match for mothers. In Indonesia, the mother's recollection of their child's inability to see at dusk or dawn was every bit as accurate as any objective measure. In fact, the mother's memory had a higher correlation to low serum vitamin A levels than the objective measures.

A Critic's Rebuke and Takeback
Sommer's initial studies with vitamin A were too good to be believed. After he reported the results in the medical journal Lancet, critics quickly said 'no way.' Some said that if Sommer had claimed vitamin A could reduce death rates by 10 percent, they would have accepted it. But Sommer's claim of reducing deaths by 34 percent was too much. One critic of Sommer's work publicly stated his findings were "too good to be true." Later he  wrote an editorial in the New England Journal of Medicine tilted, "Vitamin A - Too good not to be true."

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Sommer's primary research occurred in Indonesia

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Al Sommer's Science Life as an Action Hero


Going My Way?
When the Bangladesh Liberation War broke out in 1971, the government especially targeted intellectuals and Hindus. Sommer's research group was forced to evacuate. In a final act of service, before being evacuated with all the other westerners, Sommer made multiple trips to the border, carrying Bengali intellectuals in the trunk of his car. He often encountered road blocks manned by tough, AK47-toting militants from Pakistan's Northwest frontier along the way, forcing him to use his smile and ease of talking to spirit them through. He finally let them out where it was safe to cross the Indian border.

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Key Insight
When Sommer approached vitamin A deficiency the health field believed its only serious manifestation was in causing blindness.

At Christmas time in 1982, a year after completing the normal analysis of three studies he had created and executed in Indonesia in the late 1970s, Sommer re-examined the datasets. As he immersed himself in the information "it became apparent that something very funny was going on with the data." Sommer said to himself, "Gosh, what in the world is going on here?" Children who had night blindness seemed to disappear from the study. They wound up in the "don't know" category far more than did kids who had normal eyes. What happened to those children with their big eyes? Why did they leave the study?

"Holy cow!" Sommer exclaimed, suddenly realizing the children weren't showing up for examinations because they were dead! "I got really excited," Sommer said, "and using my little hand calculator, I redid the data by hand, going from cell to cell....What was the risk of kids with night blindness dying? What was the risk of kids with Bitot's spots dying? How about kids with spots and night blindness? Kids with normal eyes? I checked them through six intervals."

Sommer's original dataset did not measure childhood deaths because death was not thought to be related to vitamin A deficiency. By using epidemiological studies, Sommer found that children with vitamin A deficiency have a drastically higher rate of death than children with normal levels of vitamin A. Nutritional blindness, as it turned out, was not the endpoint of vitamin A deficiency, death was.

Sommer's key insight seems to have come from his asking of the dataset more than the normal epidemiologist would ask. One of his famous quotes is: "I say ‘data talk to me, tell me what you have to say.... You have to know your data, you have to smell it, you have to be in it. If you're not living inside the data you are going to miss the most interesting things, because the most interesting things are not going to be the questions you originally proposed; the interesting things are going to be questions you hadn't thought about." Rather than asking rote questions of the dataset he had prepared before the studies were executed, he used inductive logic to listen to any and everything the dataset told him. Doing so a year after the initial questions had been answered, he made his additional, and revolutionary discovery that vitamin A deficiency was more than an eye problem.

Another of his key insights was that taking vitamin A orally was as good for a child as receiving an injected shot, which was the accepted method throughout the world. This insight had begun when he ran out of injectable vitamin A. Confronted with the shortage, he didn't simply make do until a new supply was found. He designed a study that would measure if oral doses were as beneficial. That they were was revolutionary, because it meant that anyone in the world could give a child a dose of vitamin A, at a cost of less than a nickel. 

"To be fascinated with what you're doing - I went overseas and had this marvelous experience working in the field and literally having millions of people's welfare and lives hinging upon decisions that I made and investigations that I carried out and I found that extraordinarily exhilarating - that the amount of leverage, the amount of impact I could have was so much greater than I could on a one-to-one patient-physician basis. As fulfilling as that is in its own right, I made then the commitment to public health. And public health research is an area where I knew that I was going to enjoy myself."
-On the role of public health

"There's a curious paradox at the heart of public health: When it works, nothing happens. Nobody wakes up in the morning and says, 'Boy, it's great that I don't have cholera, or Isn't it wonderful that my children aren't crippled by polio?' ... We dream one day of ridding the world of blinding trachoma, death during childbirth, autism and AIDS. We know that when we realize those dreams, we shall perpetuate the paradox that lies at the heart of public health. ... [It is] a remarkable achievement ... when nothing happens."
-On the role of public health

Sommer remembers the Bangladesh smallpox epidemic as: "a horrific time. Ten million Bengali refugees were streaming back home. I was dealing with smallpox epidemics in both urban neighborhoods and dense refugee camps. The only thing you could do was pray for early detection and then mass immunization, to prevent the disease. Once someone had the disease, one-third would die. The key to success was immunizing everyone in the camps. Many refused immunization; I had to resort to holding back ration cards until they agreed to vaccination."
-On a Smallpox Epidemic

"My guiding philosophy has always been, 'Chance favors a prepared mind,' which is a quote from Louis Pasteur. My own complement to that: 'If a research project turns out as expected, you haven't learned anything.'"
-On the need to be fully prepared

"I say ‘data talk to me, tell me what you have to say.... You have to know your data, you have to smell it, you have to be in it. If you're not living inside the data you are going to miss the most interesting things, because the most interesting things are not going to be the questions you originally proposed; the interesting things are going to be questions you hadn't thought about."
-On the nature of epidemiology

"As you peel back the layers of the onion one at a time, there's always another mystery behind it, another medical detective story. Often the answers come at odd times. You don't get the insights you need - either the answer or how you are going to approach a question while you are actively thinking about it. I'll wake up at two in the morning, and I'll say, ‘Aha, I know how I'll approach that now.' Unfortunately, a lot of times in the morning what I wrote makes no sense."
-On the nature of epidemiology

"Whatever contributions I have made have largely been something other than what I started out looking for, as is the case with many contributions in science. Basically, there are lots of important issues and lots of hints that come your way. I have had that opportunity many times, that when you are concentrating on an issue in a broad perspective, some clue comes along, a hook that gives you a unique insight that you wouldn't otherwise have had."
-On the nature of epidemiology

"An area of medical research and investigation and endeavor that I didn't know very much about and literally fell in love with - epidemiology - which, in its best sense, is medical detective work. It's Sherlock Holmes played out in the medical arena and clearly has had and still has the opportunity to impact positively on the lives of literally millions of people at any one time."
-On the nature of epidemiology

"Nobody was willing to accept that two cents worth of vitamin A was going to reduce childhood mortality by a third or half, let alone when that information was coming from an ophthalmologist. A lot of people had spent their lives studying the complex amalgam of elements leading to childhood deaths, and here we are suggesting that we can cut right through this complex, causal web and give two cents worth of vitamin A and prevent those deaths. It didn't sit well."
-On the lack of acceptance of his discovering the effectiveness of oral vitamin A treatments

"All the trials came out the same, which was really quite to my amazement, given all the different cultures and environments in which the trials were done. Yet, all the studies had a 35% to 55% reduction in childhood mortality, whether you gave the capsule once every 6 months, every 4 months, or every week, or if you put a little vitamin A into something they ate once a day. It all came out essentially the same, which was quite heartening."
-On his satisfaction in successfully replicating his vitamin A studies in several other countries

"My first and most important rule is attributable to that great twentieth century philosopher, Woody Allen-‘90 percent of success is showing up.' Nothing will happen, or come to mind, if you are not around to observe or experience it. Of course not everything you observe or experience is worth a second thought, but I'd be surprised if you haven't already exchanged some nuggets of potentially brilliant opportunity-even if rare and far between-over beer and pretzels at Friday Happy Hour."
-At his last convocation speech as Dean of the Johns Hopkins Bloomberg School of Public Health, 2005

"Yogi Berra famously exclaimed, ‘When there is a fork in the road, take it.' He actually said this-I heard him on an old TV documentary. I'm still not entirely certain what Yogi meant-but I've interpreted it as a recommendation to ‘follow your nose.' At every point in my career I've chosen to do what seemed most important and most interesting at the time, never what might best position me for the next step in my career. In fact, I've never thought in terms of a career, only of a string of interesting challenges and opportunities. Might a different "fork" have been more rewarding? Perhaps. But one can never know. ‘Forks in the road' are not susceptible to randomized trials. But not taking a fork, whichever it is, leaves you stuck on the same old path."
-At his last convocation speech as Dean of the Johns Hopkins Bloomberg School of Public Health, 2005

Quotes About Sommer and vitamin A
"Dhaka changed him forever."
-W. Henry Mosley, who hired Alfred Sommer in 1970 to work in the epidemiology division of the Cholera Research Laboratory in Dhaka, Bangladesh. Mosley sent Sommer and his team to Dhaka to assess the health care needs after a massive cyclone killed more than 240,000 people.

"There are relatively few absolute, new ideas in the world. If you have one in your life, you're really something. Al Sommer has had several of them."
-Bruce Spivey, Secretary General and President-Elect, International Council of Ophthalmology.

"Over and above being a friend and mentor, I'd call him the greatest advocate of public health in our modern day."
-Keith West, The George G. Graham Professor in Infant and Child Nutrition, Johns Hopkins Bloomberg School of Public Health.

The World Bank has ranked vitamin A supplementation as perhaps the most cost-effective health intervention in all of medicine.

The UN's Declaration on the Rights of Children, framed in 1990, included the right to adequate vitamin A.

Xerophthalmia often begins with nightblindness, which in some cultures is called "chicken blindness," because afflicted children mimic chickens' inability to see at dusk.

The ancient Egyptians treated nightblindness with animal liver (where vitamin A is stored) 3,500 years ago.

Three ounces of beef liver provide 545 percent of the recommended vitamin A daily value, and one-half cup carrot juice, 450 percent. One cup of whole milk provides just 5 percent, and one peach only 6 percent.

Vitamin A deficiency reduces the body's ability to fight infection, which may lead to respiratory distress, such as pneumonia, and diarrheal infections.

A very high intake of provitamin A carotenoids, the type of vitamin A found in colorful fruits and vegetables (carrots, spinach, kale, cantaloupe...) can turn the skin yellow - but it is not harmful to your health.

Casimir Funk, a Polish biochemist, is credited with the discovery of vitamins. He isolated what would come to be known as vitamin B1 (Thiamine) in brown rice, which had been shown to have a protective effect against beri-beri. He originally called the substance vitamine, because it contained an amine group, and then theorized these newfound substances could also cure other diseases.

Carl E. Bloch, a pediatrician at the University of Copenhagen, is credited with the discovery of vitamin A. He noticed a difference in the health of two groups of children, housed in separate buildings, and began to investigate. He concluded the sickly group of children were not receiving sufficient fat intake, a factor he called "fat-soluble accessory factor A," later to become known as vitamin A.

Statistics About Vitamin A Deficiency
Vitamin A deficient children have a 23% greater risk of dying from the measles, diarrhea or malaria.
Over 80 percent of the vitamin A intake in developing countries is from non-animal sources.
The established goals call for providing children 6-59 months with 2 rounds of vitamin A annually.
UNICEF classifies 61 countries as "high mortality" countries due to vitamin A deficiencies.
UNICEF lists 35 additional countries as being "priority countries."
As of 2005, all major regions of the world exceeded 70 percent compliance in administering 2 annual doses.
Globally, the number of children fully protected rose from 16 percent, in 1999, to 72 percent in 2005.
Nutritional blindness responds to treatment with vitamin A within 24 hours.

Education
1963 - Bachelor of Science (BS), Union College.
1967 - Medical Diploma (MD), Harvard Medical School.
1973 - Masters of Health Science (MHS), Johns Hopkins School of Hygiene & Public Health.

Professional Training
1967-1969 - Medical Intern and Resident, Beth Israel Hospital, Harvard University.
1972-1973 - Fellow in Epidemiology, Johns Hopkins School of Hygiene & Public Health.
1973-1976 - Resident and fellow in Ophthalmology, Wilmer Eye Institute, Johns Hopkins Hospital.

Certification
1968 - Diplomate, National Board of Medical Examiners.
1977 - Diplomate, American Board of Ophthalmology.

Family
Wife - Jill
Son - Charles
Daughter - Marni

Sommer's Other Major Discoveries
Measles
Sommer also proved that vitamin A could fight measles, since, as he says, "measles is a viral disease that infects and damages epithelial tissues throughout the body." He found a missionary physician in Tanzania who reported that many children with measles were going blind. He set up a randomized trial with vitamin A and demonstrated that children receiving vitamin A supplementation were 50 percent less likely to die.

Vitamin A supplements and mortality related to measles: a randomised clinical trial. Br Med J 1987;294:294-296. Barclay AJG, Foster A, Sommer A. 

Smallpox Vaccination is Effective even after Exposure
Along with thousands of others, Sommer participated in the smallpox vaccination campaign that helped eradicate smallpox worldwide. While conducting research in Bangladesh in 1972, Sommer discovered that vaccination against smallpox was effective even after the initial exposure. Those vaccinated within five days were completely protected, and those vaccinated within eight days were able to avoid death. 

An Effective Childhood Malnutrition Measurement
Sommer says that he's "compulsively driven to collect data without thinking about it." When Sommer was in Bangladesh, he found an incomplete nutritional study that involved measuring children's upper arms. At the time, nutritionists were trying to develop a means of accurately measuring childhood malnutrition. Standard measures, like measuring body fat or protein content of blood, were too technically difficult for application in the developing world. Weight-to-age ratios were also ineffective, because it was often difficult to discover a child's exact age. In the 1960s, Quaker medical missionaries in Nigeria had developed a physical test in which they measured the circumference of a child's upper arm (a good indirect measure of muscle mass) against a height table to determine who might be undernourished using a QUAK stick. A decade later, health workers in East Pakistan had accumulated arm and height measurements for 8,292 Bengali children. But, there had been no follow up. Sommer decided to track as many of the children down as he could.

Combing through death records, he made a startling discovery: During the first month after the children had their arms measured, 1 to 4-year olds in the lowest nutritional category were at almost 20 times greater risk of death than those whose ratio was normal. He found that predicting the mortality of children could be as simple as measuring their arms! His findings were so startling he had trouble getting the study published.

Sommer A, Loewenstein M. Nutritional status and mortality. A prospective validation of the QUAC stick. Am J Clin Nutr 1975;28:287-292.

Glaucoma's Magic Number Debunked
Sommer is one of the more prominent members of a movement to bring modern medicine into evidence-based science. That means you have to have real evidence - not guesses, not anecdotes, not assumptions - before you come to conclusions. Believe it or not, there is no statistical support for some of the things doctors do or believe. For instance, there is the problem of magic numbers. The magic number in determining if a patient has glaucoma is 21 millimeters of mercury pressure in the eye, the intraocular pressure. If the pressure is higher than 21, you have glaucoma. If it is less, you don't. Ophthalmologists could always find patients with more pressure than 21 who show no signs of glaucoma, and people with pressures below 21 who have optic nerve damage.

Sommer was not satisfied with such an inexact variable, so he executed a study in Baltimore that demonstrated the magic number was of little use. Success or failure in treating glaucoma did not depend on the pressure relative to any number, but on what was happening to the optic nerve. The magic number of 21 still isn't dead, but there now is less emphasis on it. Sommer's study gradually found its way into the common wisdom.

The Increased Risk of Developing Glaucoma in Blacks
Because his glaucoma study was done in a racially mixed neighborhood of east Baltimore, he also ferreted out another unknown variable. He found that blacks were four times more likely to get glaucoma than whites, for reasons unknown.

Vitamin A Supplementation's Ability to Reduce Mother's Childbirth Mortality 
Sommer has continued to study vitamin A. His latest findings demonstrate that vitamin A supplementation to mothers lowers childbirth death rates.

Alfred Sommer's Life: A Timeline
1942 - Born in Brooklyn, New York - moved to Queens as a teenager.
1963 - Bachelor of Science (BS), Union College.
1963 - Married to Jill.
1967 - Medical Diploma (MD), Harvard Medical School.
1967-1969 - Medical Intern and Resident, Beth Israel Hospital, Harvard University.
1967 - Began work with the CDC-Epidemic Intelligence Service-in Dacca, Bangladesh.
1968 - Diploma, National Board of Medical Examiners.
1969 - Birth of his son, Charles.
1970 - Assessed survivors' needs in East Pakistan (Bangladesh) following massive cyclone.
1971 - Birth of his daughter, Marni.
1971 - Helped Bengali intellectuals escape during the early stages of the Bangladesh Liberation War.
1972 - Headed team to stop the outbreak of smallpox in the newly formed nation of Bangladesh.
1972 - Discovered the smallpox vaccine works even for those already exposed.
1972 - Confirmed the measurement of arm circumference is an accurate predictor of death among children.
1972-1973 - Fellow in Epidemiology, Johns Hopkins School of Hygiene & Public Health.
1973 - Masters of Health Science (MHS), Johns Hopkins School of Hygiene & Public Health.
1973-1976 - Began to learn about nutritional blindness and set up studies in Haiti and El Salvador.
1973-1976 - Resident and fellow in Ophthalmology, Wilmer Eye Institute, Johns Hopkins Hospital.
1974 - Attended the first international conference on nutritional blindness in Indonesia.
1976-1979 - Nutritional Blindness Prevention Project-three years studying nutritional blindness in Indonesia.
1976 - Discovered that vitamin A taken by mouth is as effective as an injection, a major breakthrough.
1977 - Diploma, American Board of Ophthalmology.
1979-1980 - Spent one year in London analyzing the data from his Indonesian study.
1980 - Returned to the United States to become a professor at Johns Hopkins.
1982 - Revisited his Indonesia data and discovered that vitamin A deficiency is a major childhood killer.
1982 - Discovered vitamin A deficiencies were a leading cause of childhood deaths in developing nations.
1983 - Published results of Indonesian study, linking vitamin A deficiency and higher death rates, in Lancet.
1983 - Onward-developed additional studies to confirm the importance of vitamin A to health.
1980-1990 - Director, Dana Center for Preventive Ophthalmology, Johns Hopkins University.
1985 - Launched the Baltimore Eye Survey, the first community-based eye survey of adults.
1987 - Published study demonstrating that vitamin A doses lower mortality for childhood measles.
1990-2005 - Dean, Johns Hopkins Bloomberg School of Public Health.
1991 - Published results dispelling the magic number of ocular pressure as a definitive sign of glaucoma.
1991 - Published results indicating blacks have a much higher rate of glaucoma than whites in the U.S.
1999 - Published a study showing that vitamin A supplementation aids in pregnant women's survival.
2002 - Chaired the Expert Group on Health for the World Economic Forum's Global Governance Initiative.

Discovering Vitamin A
Casimir Funk
A Polish biochemist, Funk is credited with the discovery of vitamins in 1912. He isolated what would come to be known as vitamin B1 (Thiamine) in brown rice, which had been shown to have a protective effect against beri-beri. He originally called the substance vitamine, because it contained an amine group, and then theorized these newfound substances could also cure other diseases.

Elmer McCollum and Marguerite Davis
Working at the University of Wisconsin, in 1913, Elmer McCollum and Marguerite Davis discovered both Vitamin A and B. They at first called it "fat-soluble factor A," since it was found in milk and fats. Earlier, Casimir Funk had named unknown nutrients in foods vitamines, because they were vital and amines. McCollum and Davis wanted to use letters, but opposed Funk's name because these nutrients were not true amines. The name was changed to its current spelling in 1920.

Carl E. Bloch
A pediatrician at the University of Copenhagen, Bloch discovered the importance of vitamin A to health. In 1917, he noticed a difference in the health of two groups of children, housed in separate buildings, and began to investigate. He concluded the sickly group of children were not receiving sufficient fat intake, which contained vitamin A. In the western world, this led to children being encouraged to drink buttermilk, or to take cod liver oil. Since this was so successful, the importance of vitamin A to children came to be ignored, and then forgotten by nutritionists. As Sommer says, "a profound amnesia appears to have settled over the broader context of vitamin A deficiency once it ceased to be a major concern of wealthier nations."

Books about Sommer
Scientists Greater than Einstein: The Biggest Lifesavers of the Twentith Century. Linden Publishing, 2009.

Awards
Helen Keller Foundation Prize for Vision Research, 2005
The Pollin Prize in Pediatric Research, 2004 (Dr. Sommer was the first individual researcher to receive the Pollin Prize. Previously, the award had gone to teams of researchers.)
Thomas E. Hobbins Health Care Justice Award, Maryland Health Initiative, 2003
Warren Alpert Foundation Research Prize, Harvard Medical School, 2003
Lucien Howe Medal, American Ophthalmological Society, 2003
Special Recognition Award for Leadership, Association for Research in Vision and Ophthalmology (ARVO), 2002
Danone International Prize for Nutrition, 2001
Bristol-Myers Squibb/Mead Johnson Award for Distinguished Achievement in Nutrition Research, 2001
Gold Jose Rizal Medal, Asia Pacific Academy of Ophthalmology, 2001
F. Parke Lewis Lifetime Achievement Professional Service Award, Prevent Blindness America, 2001
E.H. Christopherson Award, American Academy of Pediatrics, 2000
Albert Lasker Clinical Medical Research Award, 1997
Helmut Horten Medical Research Award, Helmut Horten Stiftung, Switzerland, 1997
Prince Mahidol Award for International Contributions to Medicine and Public Health, Thailand, 1997
Charles A. Dana Award for Pioneering Achievements in Health, 1988
National Academy of Sciences, elected 2001
Institute of Medicine, elected 1992

Links on the Scientist & Science
Johns Hopkins Gazette Article
https://hub.jhu.edu/gazette/2013/july/this-month-books-alfred-sommer/
Alfred Sommer's Wikipedia Page
https://en.wikipedia.org/wiki/Alfred_Sommer
Vitamin A's Wikipedia Page
https://en.wikipedia.org/wiki/Vitamin_A