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GENS1111 – Big Fat Myths Lesson 1: Fat Limits 1. Introduction In this lesson you will be learning about the limits of weight loss to address the question people are really asking: How much weight can we lose, and by what method? We're going to explore three main weight loss methods and famous dieters who have taken these methods to the extremes. 1. Eating less 2. Moving more 3. Eating ‘healthy’ or ‘clean’ foods In doing so, this lesson seeks to bust the myths that surround weight loss strategies and well coined weight loss phrases, thereby providing an insight into what is actually required if weight loss is to be successful.

2. Losing Weight by Eating Less Fasting to lose weight has been used for hundreds of years; however, in today’s society, people feel as if their world is ending when they feel hungry. This section will show us that we certainly don’t need to panic when we begin to feel hungry. In fact, a little fasting can even be good for you. Keep in mind that the outcome of a fast can vary significantly due to the methods used and overall goals.

“I fast for greater physical and mental efficiency” – Plato

Fasting is as old as the hills. Hippocrates, Socrates, and Plato all did it, and total abstinence is still revered in many of the world’s major religions. In the late 1800s, before the ‘good old days’ of radio and television, not eating became a bizarre form of performance art.

 2.1. Extreme Fasting Signor Giovanni In 1890, Signor Giovanni Succi planned to undertake a 45 day fast as part of performance art in New York that allowed the public to ‘view’ Succi 24 hours a day. Succi had a reputation for telling tall stories, and two spells in a mental asylum added nothing to his credibility. To prove his believability, Succi travelled to Florence in 1888 and submitted himself to the laboratory of a distinguished physiologist called Luigi Luciani. Luciani took a raft of measurements while Succi fasted under the close scrutiny of physicians, medical students, citizens and the press. Succi was 165 centimetres tall and weighed 63.3 kilograms at the beginning of the fast. He lost 12.9 kilograms in 30 days, weighing in at 50.4 kilograms when it ended.

Succi being examined by physicians after his fast.

The fast only lasted for 35 days and ended with Succi ‘exhausted, his nerves shattered and his tissue almost gone.’ He would go on to perform more than 30 fasts of 30 days’ duration between 1886 and 1907, in Paris, Milan, Zurich, London, Boston and New York, to name just a few. Succi received a diploma from Accademia Medico-Fisico Fiorentina to certify his abilities and carried on fasting for money around the world, often cooperating with scientists who eagerly collected his faeces and urine for scientific analysis. David Blaine

Blaine hosted over River Thames in a glass box. In 2003, a perspex box containing the American illusionist, David Blaine, was hoisted above the River Thames in London where he remained for 44 days without food. Blaine's was borderline obese prior to the fast and lost 24.5 kg (25% of his original body weight).

Blaine recovering in hospital after his fast. The world had clearly forgotten all about the ‘hunger artists’ of the past because nobody appeared to have a clue if a human being could survive that long without food!

Now we know the fasting limits of a relatively 'healthy' man, have you ever wondered what would happen if a very obese man simply stopped eating? How many days do you think someone can last without food?

 2.2. Medically Supervised Extreme Fasting In 1965, a 27-year-old Scotsman named Angus Barbieri undertook a medically supervised fast that lasted 382 days! He ate no food, lost 125 kgs, and received no known ill effects. The fast wasn’t originally planned to last so long. The supervising doctor stated that 'Barbieri adapted so well and was eager to reach his ‘ideal weight’ so the fast was continued'. It is important to note that Barbieri was under full, proper medical supervision to ensure that key vitamin and mineral levels were maintained.

Barbieri before and after his fast. Image Source: Flickr (CC BY-NC-ND 2.0) Stewart, W.K. et al., 1973, Postgrad Med J, 49(569):203-9 Barbieri drank only ‘non-caloric’ fluids, such as tea, water, soda water and coffee and took some vitamin and mineral supplements at various times of the fast. No other medications were prescribed.

Table: Barbieri Fasting Statistics Starting weight

207 kg

Final weight

82 kg

Total weight loss

125 kg

Average weight loss

330 g/day

Along with Angus Barbieri, 13 other patients fasted to lose weight as part of the Glaswegian Study. Their fasts lasted for between 25 and 249 days and all resulted in weight loss. Of the 13 other patients, total weight loss ranged from 4 to 70 kg. The rate of weight loss, however, was very similar to Barbier's 330 g/day. Although the patients in the Glaswegian study were initially skeptical about their ability to endure such a prolonged fast, after a few days, they ‘spontaneously commented on their increased sense of well being, and in some, this amounted to frank euphoria’. There was no detectable physical or mental fatigue, according to the doctors, nor were respiratory rate, body temperature, sleep, or menstruation function altered. Only 3 patients experienced side effects! What was more impressive was the surprising ‘sense of well being’ the patients reported during their fasts, an unexpected clinical observation. Eating less does result in weight loss; however, it must be noted that the success of the fast was due to regulated medical supervision. Therefore, fasting to this degree should NOT be attempted at home.

 Therapeutic Fasting Angus Barbieri broke all the records but his fast was not the first of its kind. Therapeutic fasting was used to treat diabetes before the advent of the insulin injection in 1922, proposed as a potential treatment for obesity in 1915, and also proved to be an effective treatment for some forms of epilepsy. Therapeutic fasting in the form of extremely low carbohydrate diets otherwise known as 'ketogenic' diets is currently used to treat epilepsy in children, who can experience 30 - 40% fewer seizures. Odour of Sanctity One of the well-known side effects of fasting is the sweet-smelling odour of pears on the exhaled breath. The odour is acetone, one of the

three ‘ketone bodies’ produced by the liver from body fat when carbohydrate reserves run low.

The aroma has been called the ‘odour of sanctity’ because it would have been noticeable on the breath of pious people undertaking religious fasts. Fasting and party drugs An intriguing link may exist between the sense of wellbeing experienced by fasting patients and the euphoria of revelers who take the party drug GHB (also known as liquid ecstasy, fantasy, GBH and ‘grievous bodily harm’).

During starvation and extremely low-carbohydrate diets, the liver also produces betahydroxybuterate (BHB), a molecule that is almost identical to gamma-hydroxybuterate (GHB). Both substances have the chemical formula C4H8O3. The only difference between the two is the position of one of those eight hydrogen atoms and one of the three oxygen atoms. This intriguing similarity and the possible link between BHB and GHB were first reported by researchers at UNSW.

 2.4. Intermittent Fasting Fasting during Ramadan is an Islamic practice undertaken by healthy, adult Muslims, in which no food or water is consumed from sunrise to

sunset for a period of 1 month. Many studies have concluded that Ramadan fasting causes many physiological, biochemical, and metabolic changes in the body with numerous health benefits:   

Increased blood cell count and good cholesterol levels Decreased blood fat, bad cholesterol, and sugar levels Decreased blood pressure

 2.5. Dangers of Fasting Fasting can be dangerous. Whilst it does cause weight loss, it is by no means the safest way to lose weight, and the following example demonstrates this. In 1969, an otherwise healthy 20 year old woman weighed 118 kg when she began her 210 days therapeutic fast in a UK hospital. When she reached her target weight of 60 kg, she began eating again. After the 7th day of her return to food, she felt faint, laid down in bed, and lost consciousness. She recovered almost immediately, but after eating a boiled egg, she suffered a heart attack. Medical supervisors revived her, however, she passed away the next day. These same symptoms have been observed during the renourishment of prisoners of war, hunger strikers, and severely malnourished patients. It is now referred to as Refeeding Syndrome and has 54 known dangerous symptoms that affect the cardiovascular, respiratory, muscular, neurological, and renal systems in the body. What is Refeeding Syndrome? 

Refeeding syndrome is a serious and potentially fatal condition that can occur during refeeding. But why?

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As fasting progresses, energy levels are maintained by using the body's energy reserves, such as fat and muscle protein, but minerals such as phosphorus, potassium, and magnesium begin to deplete.

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When refeeding occurs, the body replaces the lost energy that it has consumed during the fast. Hormonal changes occur to replace the lost energy reserves, for example by stimulating fat and protein synthesis. This process requires the already depleted minerals and can result is a complete mineral deficit.

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To prevent refeeding syndrome, at-risk patients should have their mineral concentrations checked during their refeeding to ensure that they don't drop to dangerous levels. If this occurs, feeding can be stopped, and minerals can be supplemented.

While prolonged fasting produces spectacular weight-loss results, it can turn fatal without warning and should not be attempted without the close supervision of a qualified doctor. Note that fasting may also have other adverse effects on the body which cannot always be predicted, even by medical professionals. Some documented side-effects include a loss of fertility, gout and urate nephrolithiasis (a type of kidney stone).

3. Losing Weight by Moving More It's no secret that exercise will lead to weight loss, but how much? This section addresses the question 'how much weight could I lose if I never stopped moving?'. It will be shown that the 'moving-more' mantra cannot be used in isolation as a weight loss method.

 3.1. Case Study 1: Extreme moving In 1985, Yiannis Kouros won the lengthy 960 km Sydney to Melbourne Ultramarathon, which he completed in 5 days, 5 hours, and 7 minutes. Kouros ran 271 km nonstop in the first 24 hours, and after 2 days, had covered 463 km, which was a world record.

Image Source: Rontoyannis G.P., 1989, Am J Clin Nutr, 49(5): 976-

9 The Greek runner consumed Greek sweets such as baklava, pasteli, as well as chocolates, dried fruit and nuts, and fruits such as pears, grapes, apples, bananas, dates, and raisins, which he sometimes replaced with a biscuit soaked in honey or jam. Consequently, his daily carbohydrate intake averaged 95.5% of his total energy intake. Proteins made up only 1.4% and fat at 3% of his race diet.

What was surprising is that after the race, Kouros had only lost 0.5 kg! Evidently, we can see that moving more requires more energy intake. If the energy intake is balanced by the energy expenditure, then there will be no overall change in body weight. The converse is also true, although Kouros ate a stack of food, he didn’t gain any weight because of the increase in energy expenditure. Three scientists from Aristotelian University, Greece carefully monitored his every move, estimating that every day, Kouros:   

burned 32,000 kJ - 64,000 kJ drank 14 - 22 L of fluids consumed 33,000 kJ - 58,000 kJ

To put this in perspective, remember that the recommended daily intake for the average person is 8,700 kJ; Kouros was consuming 4 - 6 times the recommended intake! How does carb-loading work? After eating food, your body is able to store some of the 'excess' for use later in times of need. For example, after we eat a carbohydrate-rich meal, the excess glucose (sugar) is stored away in a different form, as glycogen, for later use when we need energy. The glycogen reserves are readily used up in a couple of hours for endurance athletes (e.g. marathon runners like Kouros). When this happens, they lack the energy to continue exercising. To avoid this, endurance athletes perform carb-loading: eating a lot of extra carbohydrates before, during, or after an endurance event that maximises glycogen storage, maintains blood sugar levels, and restores depleted glycogen levels, respectively.

 3.2. Case Study 2: No Eating or Moving What would happen if you stopped eating, but also stopped moving? Lucky for us, someone found the answer.

In 1912, Angostino Levanzin undertook a 31 day fast, where he consumed nothing but water, and remained ‘decidedly sedentary in his habits’. Without moving or eating for 31 days, Levanzin went from weighing 60.6 kg to 47.4 kg. Exercise will increase our energy expenditure to enhance weight loss efforts. However, even in the absence of exercise, reducing the number of kilojoules consumed will still result in weight loss! As we have seen, how much you eat and move is what puts the brakes on weight loss. But is there a limit on how much weight you can gain too? You can only eat so much food in one day. How quickly, then, can humans get bigger?

 3.3. Case Study 3: Extreme Eating The Massa people in central Africa have a fascinating tradition called the Guru Walla, in which young men consume copious amounts of food to fatten up over about 2 months. The aim is to grow a ‘specific silhouette, with a protruding stomach, thick buttocks and a layer of fat harmoniously distributed over the rest of the body’. The men consume an average of 30,000 - 50,000 kJ per day and engage in as little physical activity as possible. For perspective, this is similar to how much Kouros consumed to fuel his 463 km marathon!! Eating is compulsory and the ‘whole operation is considered to be painful'. The men receive food about 11 times per day, from 6 am until 4 am. They sit upright and stay very still to avoid being sick while they acclimatise to the diet, which takes about two weeks, and they may be asked to swallow whatever comes back up! The diet the Massa men consume is high in fiber and carbohydrate, and about 15% of what they consume makes it through undigested. According to the scientists who observed the practice in 1976, ‘the feeding bouts are punctuated by a good deal of vomiting, farting, defecating and urinating’.

At the end of the fattening session In a 1992 study, 9 men participating in the Guru Walla gained 12 - 23 kg in 9 weeks. That’s about 190 - 370 grams per day. For comparison, Angus Barbieri lost an average of 330 grams per day on his fasting diet. Other patients have lost between 95 - 390 grams per day during similar therapeutic fasts. Therefore, for the Massa men at least, we can say that gorging puts weight on at roughly the same rate as total fasting can remove it.

4. You Have to ‘Eat Clean’ to Lose Weight Kouros’s diet during the ultramarathon would have many of us puzzled: how is it that he consumed so much unhealthy food, but still didn’t gain weight?

In this section, the idea that we need to eat ‘clean’ foods (i.e. not ‘junk’ foods which contain high amounts of fat and sugar) in order to lose weight shall be destroyed.

 4.1. Is McDonalds the Enemy? Eating nothing but McDonald’s Food In 2005, Morgan Spurlock ate nothing but McDonald’s for an entire month, releasing his results in a documentary we love, but hate to watch, called Super Size Me.

Spurlock’s daily energy intake skyrocketed to 21,000 kJ per day, and unsurprisingly, he packed on 11.1 kg (an average of 370 g per day remember that Angus Barbieri lost only 330 g per day on his fasting diet). Spurlock gained weight because he increased his energy intake but didn’t compensate with increasing his energy expenditure. Eating nothing but Mcdonald’s, but eating within the recommended amounts John Cisna did exactly this in 2013. The science teacher consumed only Mcdonald’s food for 180 days but did not exceed 8,700 kJ per day. To ensure that he was consistent, he consumed every item on the Mcdonald’s menu at least once. Surprising his students (and most of society), Cisna lost 27kgs eating nothing but McDonald's! At this point, everyone is thinking the same thing: maybe he lost weight, but surely he was close to death? However, not only did Cisna lose weight, he became healthier! Cisna had elevated levels of blood fats, a major risk factor for cardiovascular disease, prior to the diet. After the diet, these all decreased!

Image Source: From Flickr (CC BY-SA 2.0) So has Cisna proven that Mcdonald’s is healthy? Nobody would make this claim, but if weight loss is your only objective, then it doesn’t matter what you eat, as long as it’s less.

 4.2. Are Carbohydrates the Enemy? Many people will be quick to say that although the Mcdonald's diet is high in fat and we know that Mcdonald's is 'fattening', it is actually carbohydrates that are the biggest culprit for weight gain. So, what if we ate nothing but carbohydrates? In 2010, the head of the Washington State Potato Commission, Chris Voigt ate nothing but potatoes for 60 days. Potatoes are almost exclusively carbohydrates, which is why this example is perfect for our lesson. Voigt ate 20 potatoes per day, which was the amount calculated by his dietician to ensure that he would maintain body weight.

All the potatoes Voigt consumed during his diet Have a think and decide for yourself whether Voigt gained weight or not. He was eating nothing but carbohydrates, which some say are terrible for a diet, however, he wasn't eating more than 8,700 kJ per day. To everyone's surprise, Voigt lost 9.6 kgs!

This completely busts the myth that carbohydrates are bad for weight loss. Remember, we're not recommending that you try the McDonald's diet or the potato diet at home! Over the long-term, it would be difficult to obtain the vast array of nutrients you need for optimal health. These people consulted doctors and dietitians to help them along the way.

5. Conclusion Eating Less This lesson has shown us that humans are actually able to survive for a great deal longer than we think without food. There are numerous examples of people who have controlled the amount of food they have eaten (whether that be through fasting or calorie-restricted diets) and lost weight. Moving More Energy intake and exercise go hand-in-hand. Kouros showed us that physical activity can burn a lot of kilojoules, but Kouros also consumed huge amounts of kilojoules resulting in almost no change in body weight. We live in an age that is exercise obsessed, yet has little regard for the amount of food that we consume. Therefore, we need to begin to put more emphasis on our energy intake, and not just fixate on exercise. Take home messages: 

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Humans can survive for a very long time without food, so if you’re feeling a little bit peckish, harden up – you will make it to dinnertime. People who cannot lose weight do not exist. So without food, or simply with less of it, you are guaranteed to lose weight. You don't have to hit the gym to lose weight. However, exercise can result in weight loss as it burns a lot of kilojoules, but it usually doesn't as it is also accompanied by consuming a lot of kilojoules too! One hamburger, ice-cream, or a can of sugary soft drink cannot make you fat – one a day, on top of what you normally eat and drink will. Carbohydrates and sugar are not the dietary devils some people think – too much of them, just like too much of...