‘How to Enjoy Perfect Health:’ The Roots of Intermittent Fasting

One diet trend that has attracted a lot of attention in recent years is Intermittent Fasting

Unsurprisingly, given the diet trend’s name, Intermittent Fasting, or Time Restricted Eating as it is also known, requires adherents to eat within a specific window during the day. Usually, this means following a 16:8 pattern, where an individual fasts for 16 hours and eats only within an eight-hour window. Others follow a 5:2 pattern, where one eats as they normally would for five days of the week, and restricts their intake significantly on the other two days. 

Naysayers might say intermittent fasting is simply a fancy term for intentionally skipping breakfast. But advocates of intermittent fasting in today’s wellness and fitness communities say that it is a therapeutic tool that activates your body’s ability to 'reverse your age and prevent disease.'

Fasting has a long history, with roots in various cultures and religious traditions. In religious contexts, fasting holds significance in major faiths such as Christianity, Islam, Judaism, Hinduism, and Buddhism, each prescribing specific fasting practices as a means of spiritual discipline, repentance, or self-control.

Upton Sinclair’s The Fasting Cure 

Wellness trends have a long history, and fasting as a tool for optimal health can be traced back to Upton Sinclair’s The Fasting Cure , first published in 1911. Sinclair (1878 – 1968) was an American journalist, author, and political activist. The Fasting Cure was based on articles he had written for the Contemporary Review, Cosmopolitan, and Physical Culture. 

Sinclair was not qualified in either medicine or nutrition. Wellness trends – today, and in the past – tend to focus on an individual who uses their own personal experience as evidence of the diet’s success. Their credentials are usually less important; anecdote is the preferred form of evidence. 
Sinclair described what led him towards fasting, describing an early twentieth-century version of what we might now call ‘burn-out’ – when writing his novel The Jungle, he said he worked eighteen-hour days for months on end. Where long hours and overwork might now result in a trip to the drive-through, Sinclair said he was ‘living mostly out of a frying-pan’, attributing his constant poor health – including constipation, colds, tonsillitis and headaches - to his diet habits, and evidently, his reliance on his frying pan.  

Doctors offered no real cure. With no respite in sight, Sinclair took matters into his own hands. He went to the Seventh Day Adventist sanitorium at Battle Creek, Michigan – birthplace of cornflakes in the United States, and other packaged health foods - then to Bermuda and the Adirondacks to learn about hygiene. He tried other popular diet trends such as chewing each bite up to one hundred times, otherwise known as Fletcherism, in honour of its namesake Horace Fletcher.  

When chewing his food one hundred times failed to ease his symptoms, the turning point for Sinclair came after an encounter with ‘a lady, whose radiant complexion and extraordinary health were a matter of remark to everyone’. Much to Sinclair’s surprise, this radiant picture-of-health was formerly a ‘bed-ridden invalid’ who suffered from myriad physical and mental ailments, but cured herself after a twelve day fast. Sinclair followed suit, taking no food for twelve days. Upon breaking his fast, he drank, as advised, only the juice of a dozen oranges over two days, followed by a milk diet. This diet involved drinking a glass of warm milk hourly on the first day; every three quarters of an hour on the second; and eventually every half hour.  

Sinclair’s testimonial outlining the success of the fast was compelling. The diet had not only improved his physical and mental health; he now experienced ‘boundless energy’ and whenever he had a minute to spare, he would do a headstand. He no longer relied on laxatives for regularity and was, he said, immune to colds. He had had found the key to perfect health. 

By the time The Fasting Cure was published, Sinclair’s fasting theories had already caused quite a stir internationally and in New Zealand. In 1910, the New Zealand Herald published an article detailing the trend, titled ‘How to Enjoy Perfect Health’. But Lloyd Jones, a businessman from Whanganui, helped to spread the ‘gospel’ of fasting to Whanganui where it was said to have been 'very much in vogue.'

Dr. Ulric Williams 

Whanganui was also home to another of New Zealand’s leading fasting experts, Dr. Ulric Williams (1890 – 1971), who attracted controversy for his very public condemnation of his own medical training. Williams was the author of a diet guide titled 'Hints on Healthy Living' that was sold throughout the 1930s and 1940s. By 1952, Hints on Healthy Living had sold 50,000 copies, according to one newspaper report. 

Fasting, Williams wrote, was an effective treatment for any illness. Put simply, Williams said, it would essentially ‘starve’ disease. Writing in the 1930s, Williams was particularly interested in the benefits of fasting for treating poliomyelitis, of infantile paralysis, as it was known. 

Williams theorised that polio was caused by a Vitamin B deficiency and could be cured by fasting. In taking this approach, Williams provided a cure for an infectious disease that continued to provoke uncertainty amongst scientists, and fear amongst the public. During the 1930s and 1940s, New Zealand experienced frequent outbreaks of poliomyelitis, and scientists continued to debate how it was spread. The Salk vaccine was not introduced to New Zealand until 1956. Polio was unlike other infectious diseases. Researchers had also attempted to find out why it usually occurred in children, and why it was more common in the summer months. 

Amongst this uncertainty, Williams provided a definitive solution. Children needed more Vitamin B than adults, according to Williams, and they ate more ‘rubbish’, particularly during summer, when the hot weather led to a diet of ‘ice-creams, coloured drinks, and refined starchy and sugary rubbish’. This increased the toxic load on the body, in which the polio germ could thrive. 

The cure then was through cleansing the body by fasting, or an eliminative diet. Williams’s eliminative diet allowed a warm, unsweetened lemon drink, followed by a breakfast of ‘Two varieties of fresh fruit – any seasonable kinds but not bananas.’ Nothing else at all was to be eaten. Throughout the day, one could sip on plain water, or water flavoured with fruit juice or Marmite. 

Williams also prescribed his fasting and eliminative diets for treatment of infectious and non-infectious diseases, including diphtheria, poliomyelitis, and cancer. Likewise, his fasting treatments could be used to ensure pep and vigour into old age. 

Williams’s theories provided certainty in an uncertain time, and he disseminated them through books, radio broadcasts, and health lectures, a popular past-time in the 1930s. Eventually, his controversial views courted the attention of the New Zealand branch of the British Medical Association, and he was expelled in 1936. The Medical Council attempted to take further action against him because he written columns for the Radio Record, but ultimately it was concluded that it was not illegal to be a ‘crank’.

Was this a 1930s version of combatting misinformation? The parallels to the present-day are striking. Research into the benefits of intermittent fasting is limited, yet celebrity doctors on YouTube and wellness influencers on social media promote the same benefits as their predecessors Sinclair and Williams – that intermittent fasting is the key to vitality and youth and can be used to prevent and treat both chronic and infectious diseases, including Covid 19. 

The history of fasting and wellness trends reveals a recurring pattern where individuals, sometimes lacking formal qualifications, advocate the healing powers of dietary practices, based on their own personal experiences. Upton Sinclair's early twentieth-century journey from ‘burn-out’ to vitality through fasting mirrors present-day claims about intermittent fasting's therapeutic benefits. Likewise, Dr Ulric Williams propagated fasting as a cure for various illnesses. Through intermittent fasting we can see the enduring appeal of extreme dietary measures over the decades, as a magic bullet to cope with broader concerns relating to aging, health, and disease prevention.

Author: Helen Morten

Helen is a PhD candidate in History at Waipapa Taumata Rau and the recipient of the Auckland Library Heritage Trust John Stacpoole Scholarship for 2023- 2024.

Her current PhD research explores the appeal of food faddists and diet trends in Aotearoa New Zealand from 1920- 1960, as a product of broader concerns regarding the nature of diet and disease during this period. 

Further reading:

Brenda Sampson, New Zealand’s Greatest Doctor: Ulric Williams of Wanganui, A Surgeon Who Became a Naturopath, Wellington: The Author, 1998.

Dave Asprey, Fast This Way, London: Harper Collins, 2021.

Jason Fung, The Complete Guide to Fasting, Las Vegas: Victory Belt Publishing, 2016.

Jason Fung, Life in the Fasting Lane, Alexandria NSW: Hay House, 2020.

Ulric Williams, Health and Healing in the New Age, Wellington: A.H & A.W Reed, 1949.

Ulric Williams, Hints on Healthy Living, Wellington: National Magazines Limited, 1939.

Upton Sinclair, The Fasting Cure, Pasadena, California: Upton Sinclair, 1923.