By Jane Elliott
Health reporter, BBC News
Food standards advisers are set to decide this spring if folic acid should be added to bread.
Elsie wanted to try experiments on herself
But it was in the 1940s that the idea of adding vitamins and minerals to foods first gained attention.
Elsie Widdowson and her scientific partner, Robert McCance, oversaw the first compulsory addition of a substance to food in the early 1940s, when calcium was introduced to bread.
They were also responsible for formulating war-time rationing - some experts say that under their diet of mainly bread, vegetables and potatoes, that was when Britain was at its healthiest.
Elsie, who died aged 93 six years ago, is now widely accepted as a pioneer in the field of nutrition and the importance of early nutrition on health later in life.
She did not believe in inflicting anything on someone else until she had ensured it herself.
Whether injecting herself with chemical compounds or living on a frugal diet in the Lake District, Elsie tested her science on herself.
"We did not believe that we should use human subjects in experiments that involved any pain hardship or danger, unless we had made the same experiments on ourselves," Elsie said in her biography, published in 1993.
Elsie graduated in chemistry at Imperial College, London, in 1928, gaining her PhD on the carbohydrate content of apples in 1931.
Elsie injecting herself for an experiment
But it was while learning about catering on a grand scale, before embarking on a dietetics course, that Elsie's path was truly set.
A trip to the kitchens at King's College Hospital, London, brought her into contact with Professor McCance, who was carrying out research into the best diets for people with diabetes.
The two bonded and started on a research partnership that was to span 60 years.
They studied the effect poor nutrition has in adulthood and their book The Chemical Composition of Foods, published in 1940, became the "bible" on which modern nutritional thinking is founded.
Soon after the war started, she and Prof McCance lived for weeks in the Lake District eating the diet which they thought the British should consume during World War II to maintain basic health.
They also cycled round Cambridge to study the importance of energy expenditure on diet.
Elsie washing down a subject for experiment on salt depletion
Elsie even injected herself with solutions of calcium, magnesium and iron as a means of understanding mineral metabolism and to study the body's absorption of iron.
Other experiments included washing down volunteers to collect sweat to study salt depletion and help understand the importance of maintaining fluid and chemical balance.
Elsie also proved that tender loving care could be as important as actual diet to the growth of children.
She studied children at a German orphanage where one group was scolded as they ate - and found these children did not thrive as well as other orphanage children fed the same diet.
Dr Margaret Ashwell, Elsie's biographer and member of the Early Nutrition Programming project, says that although she was best known for her rationing work, Elsie had a role to play in much of society's modern thinking about nutrition.
"She was very interested in early nutrition and what happened next. She looked at the importance of breast milk and breast-feeding," Dr Ashwell said.
"She knew that a baby was what their mother ate in pregnancy and how what the child ate in early life could influence their later health."