In the twenty first century many people would agree that more fruit and vegetables and less meat is the way to a healthy diet. Scientific studies often publish statistics comparing meat eaters with Seven Day Adventists, (SDA) because the Adventists are a group of people who have advocated and practiced vegetarianism for almost 150 years.
The reason this lifestyle came about is largely due to an event which occurred in the summer of 1863 in Michigan, USA.
In June 1863 Ellen Gould White, one of the co-founders of the SDA has a vision. She was at the home of brother A. Hilliard, at Otsego, Michigan, when (as she puts it in her own words) "the great subject of health reform was opened before me in vision".
Prior to this 'vision' physical health and diet was becoming an issue for the Seventh Day Adventist (SDA) ministers and a number of them were in poor health.
White claimed the vision was from God and that it lasted for 45 minutes, during which God was said by her to have revealed many important principles for a "health reform" movement she was to later institute in the SDA Church.
Later that year she wrote her first pamphlet "An Appeal to Mothers" which was published in 1864, in which she asked questions such as; “have you not marked the lack of healthy beauty, of strength, and power of endurance in your dear children?”
“Have you not noticed that there was a deficiency in the mental health of your children?”
“Have you not been alarmed at their disregard of parental authority, which has bowed down the hearts of their parents with grief and prematurely sprinkled their heads with grey hair?”
“It gives you pain to see your children feeble in body and mind; but does it not cause you still greater grief to see them almost dead to spiritual things, so that they have but little desire for goodness, beauty of character, and holy purposes?”
White and many of the Adventists regarded her visions as gifts of prophecy and she went on to have many visions and to write many essays and books.
According to Wikipedia's list of the best selling books of all time, her book "Steps to Christ" first published in 1892 has sold 62 million copies and her 5000 articles and 40 published books have been translated into more than 140 languages.
In 1905 White's book The Ministry of Healing was published. In the preface she wrote; It is not the creator's purpose that mankind shall be weighed down with a burden of pain, that his activities shall be curtailed by illness, that his strength wane, and his life be cut short by disease. But all too frequently the laws established by God to govern the life are flagrantly transgressed; sin enters the heart, and man loses sight of his dependence upon God, the source of life and health. Then follow the penalties of transgression--pain, sickness, and death.
The book emphasizes the link between diet and spiritual growth. It's a diet book, a self -help book, and a Christian spiritual guide all rolled into one, and it continues to be read widely to this day.