The video above entitled “Sugar: The Bitter Truth” represents a lecture by Dr. Robert Lustig, a pediatric endocrinologist and a professor of clinical pediatrics, in the harmful effects of fructose sharing metabolic similarities with ethanol, while at the same time differing completely from glucose.
In this week’s article, I would like to highlight some key points of the video and share out my points of view as well. Lastly, I strongly urge anyone to watch the video before reading this article head-on.
The hour and 30 minutes long video can be summarised into 6 main parts; The Obesity Epidemic and increasing caloric intake, Origins of the high sugar diet (with High Fructose Corn Syrup), Reasons for Prevalence, Biochemistry of Fructose, Health Implications, and Resolution.
The Obesity Epidemic
Let us begin firstly with the Obesity Epidemic, in many developed countries around the world, the rates of obesity and diabetes have been increasing. In a 2010, National Health Survey done in Singapore, the rates of obesity have been increasing since 1992 across Singaporeans of all ethnic, gender and age groups. 
Many of the strategies suggested to prevent obesity revolves around the ‘calorie in and calorie out’ model (Eat less and exercise more), yet as mentioned in the video, a calorie is not a calorie. The pathway that a certain calorie is metabolised will then determine its impact in weight gain. So in other words, not all carbohydrates, fats and proteins are metabolised in the same way.
In referencing back to the video lecture at ‘minute 9:00’, it was shown that the caloric intake had increased by comparing children ages 2 – 17 in (1989 – 1991) vs (1994 – 95), in a study done by the United States Department of Agriculture (USDA).
This had led to a suggestion that leptin (The satiety hormone) is out of tune with the body’s systems, for why is it we are eating more to reach the same level of fullness?
What about fat consumption? In 1982, the American Health Association, American Medical Assocation and the US Department of Agriculture had managed to have Americans reduce their fat consumption from 40% to 30% (Referring back to minute ’10:00′). So with the expectations of rates of obesity to decline, it had instead increased rapidly ever since.
To put it into Singapore’s context, with many Singaporeans understanding that eating too much saturated fat can lead to cardiovascular problems (especially trans-fat) and health authorities advising to moderate fat consumption,  why is it that the rates of obesity in Singapore are still increasing? Can it likely be our sugar consumption?
Prevalence of Sugar and Its Origins
At the minute mark of (23:45), Dr, Lustig describes the ‘perfect storm’ scenario that has led to the high advent of sugar productions, post World War II. The first being Food Prices, Richard Nixon, the 37th President of the United States, who was running for the 1972 elections had wanted food prices to stabilise. In doing so, methods were taken to make food cheap, leading to factor 2.
The advent of High Fructose Corn Syrup (HFCS), which had entered U.S. Markets in 1975. In my first article on Corn, corn experiences heavy subsidies and is cultivated on large acres of land. This means that there is an abundant supply of corn that can be readily processed into Corn Syrup, leading to a very cheap supply of a sweetener that is better than sugar – sucrose (in sweetness).
The last reason is due to the reduced consumption of fat. When food manufacturers had experienced the demand of consumers and health authorities wanting more low-fat products in markets, they had to add more sugar in to substitute fat. This is because by removing fat, the palatability of the food product severely deteriorate and fat plays a crucial role in the texture, mouth-feel and taste in food.
How did Sugar Prevail?
The journey of sugar and HFCS to integrate itself into many products lies in affordability, availability and its technical properties (Sweetener and browning-agent). But the heart of sugar’s prevalence lies in its demand (Low-Fat food products – Reason #3), all due to the work of the “Seven-Countries Study”, done by Ancel Keys.
In summary, the 1958 Seven-Countries Study had shown that of the 7 countries looked into, a relation was shown that increased consumption of fat was related to an increase likelihood of cardiovascular disease. However, there were some criticisms afterwards that suggested the findings of the study was flawed. 
This is because of the 7 countries that Ancel Keys selected, there remains a total of 22 countries not involved, why was this the case? Certain countries such as Holland and Norway ate alot of fat but had little heart disease while in Chile, fat consumption was low and yet heart disease was high.  Was the data used cherry-picked?
Moreover as mentioned in the video, in a multi-varied regression study which involves taking data, finding certain relations and factoring an outcome, Keys had mentioned only saturated fat and its relevance to coronary heart disease but ignored the sugar aspect. (Lacking a counter study to see if absence of sugar would provide the same results)
In fact, many scientists such as John Yudkin, a British physiologist and nutritionist had argued at the time that sugar was the cause of heart disease in the study, not fat. He had written ‘Pure White and Deadly’ [PDF link below] shortly after to warn the public about the devastating effects of sugar, though I supposed the message could have been suppressed as food companies were readying for more usage out of sugar as a sweetener or that the media had gotten more interested in Key’s study instead.
Either way, with some strong criticisms and controversy about the ‘Seven Countries study’ and the fact that many health authorities globally have taken up the study’s conclusion that consumption of saturated fat leads to heart disease, could have our attention been diverted at the wrong cause?
“Fructose is a Poison”
The biochemistry of fructose.. when I had watched Dr. Lustig’s lecture video several years ago, I was taken aback that fructose metabolism was more similar to ethanol (beer) than to glucose. In fact, in a book written by David Gillespie titled “Sweet Posion: Why Sugar Makes Us Fat“, it reaffirms what the video had said about the metabolic harms of fructose.
Fructose is called a poison basically because it is only metabolised by the liver, not registered by the brain and it causes a list of chronic metabolic diseases. In a summarised version of the Dr. Lustig’s explanation on the biochemistry of fructose (57:25), fructose produces more metabolic waste than glucose.
This leads to an excess of citrate produced during respiration that are converted into Very Low Density Lipoproteins (VLDL) which can cause dyslipidemia (abnormal amount of blood lipids), lots of phosphorylation leading to uric acid production that can cause gout and hypertension. In addition, the muscles and liver can become Insulin Resistant (IR), with free fatty acids produced interfering with insulin signaling pathways in the muscles and JNK1 (protein kinase) deactivating insulin in the liver.
Lastly, the obesity factor is present when more energy is added into the fat cells as a result of fructose metabolism which also leads to weight gain. For the brain does not register any fructose intake and with its metabolism leading to a high amount of insulin produced for the muscles and the liver, leptin (the satiety hormone) is suppressed and the brain thinks it is starving despite having consumed calories from fructose. This can lead to an unhealthy cycle of eating that can become an addiction.
In the concluding message of the video, Dr. Lustig had mentioned of 4 life-style interventions that he does in his to help type II diabetic patients recover from their illness. The 4 steps are:
1) Remove all sugar liquids (Sodas and Juices)
2) Eat all carbohydrates with fiber
3) Wait 20 minutes for second portions
4) Balance screen time with physical activity
The reason as to why sugar liquids are so potent in causing harm to the body is by how readily it is absorbed. Sucrose (table sugar) when broken down into its constituents glucose and fructose spikes blood sugar sharply (glucose metabolism) while fructose in its own way causes a metabolic havoc similar to that of alcohol.
Fiber is in itself as mentioned in the video, an essential nutrient. It reduces the rate of intestinal carbohydrate absorption which reducing sharp insulin spikes while allowing the brain to register that it is full by allowing leptin hormones to register. This is why fruit juice is not as healthy as it is publicised to be with much of the fiber extracted and the juice is consumed in a sweetened liquid sharing sugar levels with that of a can of soda.
Lastly, balancing screen time with physical activity is in a way to rid ourselves of our sedentary lifestyles. Exercise plays a major role in improving the metabolic illnesses in diabetics for it improves the muscles’ sensitivity to insulin while reducing stress levels. It allows the citric acid cycle to occur faster, which reduces the citrate waste responsible for the production of unhealthy lipids (VLDL). The main reason is NOT to burn calories.
Having condensed what Dr. Lustig had mentioned in his video lecture, why is sugar, (specifically fructose) still under the Generally Recognised As Safe (GRAS) status? It is known to cause metabolic illnesses and serve no nutritive benefits only that of energy in itself. The United States Department of Agriculture (USDA) will not remove fructose of the ‘GRAS’ status for it does not function as an acute toxin, but as a chronic toxin. Requiring thousands of dosages before an illness occur, that is actually facing to reality.
So the take-away message of this article is that a calorie is not a calorie, fructose is metabolised largely differently than glucose and to treat fructose similarly to how you would treat beer (strong moderation in consumption). The only difference is that beer is taxed and controlled by governmental bodies to reduce consumption by increasing prices, while fructose remains cheap and readily available at your nearest mini-mart for a dollar. Literally, a Poor Man’s Alcohol.
John Yudkin’s book [PDF] on Pure White and Deadly
- Goh. L.G., Pang. J., 2012. Obesity in Singapore, Prevention and Control. The Singapore Family Physician. [online]. Mar 2012. Vol 31. No. 1. Available from: http://cfps.org.sg/publications/the-singapore-family-physician/article/71 (Accessed 21/3/2016).
- Singapore Heart Foundation, 2012. Limiting Fat Intake [online]. Available from:
http://www.myheart.org.sg/article/a-heart-healthy-lifestyle/diet-and-nutrition/limiting-fat-intake/215 (Accessed 21/3/2016).
- Rebecca, 2012. The Myth of Cholesterol and Heart Disease [online]. Available from: http://www.drrebecca.com/2012/02/myth-of-cholesterol-and-heart-disease.html (Accessed 21/3/2016).
- Gunnars. K., 2013. Modern Nutritional Policy is Based on Lies and Bad Science [online]. Available from: https://authoritynutrition.com/modern-nutrition-policy-lies-bad-science/ (Accessed 21/3/2016).
- Chan. L.E., 2016. Will a sugar tax work in Singapore? [online]. Available from: http://www.channelnewsasia.com/news/singapore/will-a-sugar-tax-work-in/2612888.html (Accessed 21/3/2016).