McGill Open Online Course
"Food for Thought"
The year was 1982. "Food for Thought", a new and innovative course conceived by Drs. David Harpp, Joe Schwarcz & Ariel Fenster. Designed to provoke some thought, separate fact from fiction and of course, digest everything there is to know about food. And now, 15,000 students later, you too can take this course. FOR FREE. That's right. McGill presents its very-first MOOC (massive open online course), & the McGill Office for Science and Society (OSS) is up at bat. Are you ready for some Food for Thought? Click here to register.
The reviews are in! 4.96/5!! Click here!
Week 7: After artificial sweeteners…sweetness enhancers
The company Senomyx is developing a sweetness enhancing ingredient. The compound called Sweetmyx, is not sweet by itself, but it increases the taste of sugar in products with reduced levels of sucrose or fructose. The research involved identifying specific human sweet taste receptors and developing molecules capable of binding to these sites. The receptors thus stimulated respond to lower levels of sweetener.
Sweetmyx is developed in partnership with PepsiCo for use in their carbonated soft drinks whose sales have declining over the last few years. Decline caused by the controversies associated with the high sugar content in regular drinks and the use of artificial sweeteners in diet drinks. The developer of Sweetmyx hopes that it will be adopted by consumers looking for a full sugar taste but with fewer calories. This may take some time. On March 12 the company announced with great fanfare that it had received the GRAS (Generally Recognized As Safe) by an expert panel of the Flavor and Extract Manufacturer Association. A GRAS designation, which needs to be recognized by the FDA, means that the ingredient does not require further premarket testing.
Unfortunately for Senomyx, the same day the FDA sent a press release stating had not been informed and had not approved the GRAS status for Sweetmyx. The shares of Senomyx that had gone up 25% on the initial announcement went right back down.
Week 6: The Pleasure of Chocolate Tasting
For chocolate lovers the tasting process is an experience not unlike the one associated with wine appreciation. It involves a number of steps that bring out the complexity of what is referred as "The food of the Gods". The tasting has to be done on its own so as not to be affected by the remnants of a previous food. You don't want the chocolate to taste like pepperoni pizza. Never taste chocolate just out of the fridge as the cold temperature kills the taste. Examine the surface. It should be free of white marks (known as bloom). This is caused by the migration of sugar and fat to the surface. The presence of bloom suggests poor manufacturing or storage. Then smell the chocolate. There are more than 500 chemicals in chocolate and aroma is an important component of flavor. Break a piece off. It should sound as a sharp "snap". If the sound is muted it means that the chocolate was either too warm or not properly tempered. Place a piece on the surface of the tongue and let it melt slowly. The melting point of chocolate is 36 0C, one point above body temperature and the slow melting will allow the different flavor components to be expressed in turn. Then repeat the experience as often as you can. As you acquire expertise you will be able to distinguish different varieties and different places of origin and impress your friends by arguing the respective merits of a Criollos, Forasteros and Trinitarios.
Week 5 Update: Organic foods
So, do consumers who buy “organic” avoid pesticides? Hardly. Organic farmers are allowed to use a number of pesticides as long as they come from a natural source. Pyrethrum, an extract of chrysanthemum flowers, has long been used to control insects. The Environmental Protection Agency in the U.S. classifies it as a likely human carcinogen. There you go then, a “carcinogen” used on organic produce! Does it matter? Of course not. Just because huge doses of a chemical, be it natural or synthetic, cause cancer in test animals, does not mean that trace amounts in humans do the same. Furthermore, pyrethrum biodegrades quickly and residues are trivial. But that is the case for most modern synthetic pesticides as well! And how about rotenone? This compound was discovered in the 1800s in the extracts of the root of the derris plant. Primitive tribes had learned that the ground root spread over water would paralyze fish which then floated to the surface. Rotenone is highly toxic to humans and causes Parkinson’s disease in rats. It can be used by organic farmers to control aphids, thrips, and other insects on fruit. Residues probably pose little risk to humans, but synthetic pesticides with the same sort of toxicological profile have been vilified.
Organic farmers are also free to spray their crops with spores of the Bacillus thuringiensis (Bt) bacterium which release an insecticidal protein. Yet, organic agriculture opposes the use of crops that are genetically modified to produce the same protein. Isn’t it curious that exposing the crop to the whole genome of the bacterium is perceived to be safe, whereas the production of one specific protein is looked at warily? The truth is that the protein is innocuous to humans, whether it comes from spores sprayed on an organic crop or from genetically modified crops. True, organic produce will have lower levels of pesticide residues but the significance of this is highly debatable.
A far bigger concern than pesticide residues is bacterial contamination, especially by potentially lethal E. coli 0157:H7. The source is manure used as a fertilizer. Composted manure reduces the risk, but anytime manure is used, as of course is common for organic produce, there is concern. That’s why produce should be thoroughly washed, whether conventional or organic. Insect damage to crops not protected by pesticides often leads to an invasion by fungi. Some fungi, like fusarium, produce compounds which are highly toxic. In 2004 two varieties of organic corn meal had to be withdrawn in Britain because of unacceptable levels of fumonisin, this natural toxin.
Week 4 update:
Research goes on in thousands of laboratories around the world as we all know. Scientists attempt to sort out a myriad of problems not the least of which are associated with food consumption and the consequences.
One very specific problem involved detailed research of star fruit (Carambola). It is called star fruit because it has a five-sided overall shape that delivers pentagonal-looking slices. They are not high in calories and have considerable fiber, antioxidants and flavonoids. They are grown in Southeast Asia, Australia and Florida.
The issue with this fruit is that people with kidney disease can become confused and sometimes have hiccups, seizures and vomiting sometimes resulting in death when consuming this fruit. It is now known that star fruit contains a toxin named caramboxin that can be easily metabolized by a healthy kidney but diseased kidneys cannot rid the body of this substance. Cramboxin interferes with proper neurotransmitter activity. The workers suggest that this molecule could be useful in studying neurotransmitter receptors now that the cause of this disorder is better understood. The molecule caramboxin is a close analog of a common amino acid, phenylalanine. This research was carried out at the University of Sao Paulo in Brazil.
Soon, the macronutrient section will begin and one of the considerations will be the topic of trans fat. These days it is difficult not to hear about this particular form of the fat family. New York City banned trans fat use in 2007 but certainly this regulation has not been adopted across the U.S. Fats are composed of saturated and unsaturated molecules along with the trans type. There are essentially two types of trans fat- “artificial” and “natural”. Interestingly, in this instance, the trans fat that is found in butter and some meats and cheese have been independently shown not to be harmful for consumption.
The discussions in the press center on the “artificial” variety in that these are “accidently” formed when unsaturated fats are treated with elemental hydrogen in an effort to prepare the saturated variety by a process of partial hydrogenation. Research over the last several years has shown that this version of the trans fat family increases the risk of coronary heart disease. The Food and Drug Agency (FDA) suggest that a ban on this type of molecule could prevent up to 7,000 deaths a year (in the United States).
When the FDA required the labeling of fats in 2006 and considering the health concerns of the “unnatural” trans fats, many food manufacturers began to substitute other (possibly) less-damaging fats. However, trans fats were still found in some microwave popcorn and other types of cookies and biscuits including numerous baked goods. As a conclusion to this complex usage of trans fats, in November, 2013 the FDA banned the use of partially hydrogenated oils in food (the process that produces trans fat). This regulation should strongly contribute to better health. Nonetheless, many processed foods contain much salt and sugar in an effort to maintain the taste levels that sell the product. It is possible regulations concerning the use of these specific “foods” will be enacted in the future.
Week 2 Update: Vitamin names
When the mechanized rice mill was introduced in Asia, a new disease that came to be called “beriberi” cropped up. Beriberi means “weakness” in the native language of Sri Lanka, and describes a condition of progressive muscular degeneration, heart irregularities and emaciation. Kanehiro Takaki, a Japanese medical officer, studied the high incidence of the disease among sailors in the Japanese navy from 1878-1883. He discovered that on a ship where the diet was mostly polished rice, among 276 men, 169 cases of beriberi developed and 25 men died during a nine-month period. On another ship, there were no deaths and only 14 cases of the disease. The difference was that the men on the second ship were given more meat, milk and vegetables. Takaki thought this had something to do with the protein content of the diet, but he was wrong.
About 15 years later a Dutch physician in the East Indies, Christiaan Eijkman, noted that chickens fed mostly polished rice also contracted beriberi but recovered when fed rice polishings. He thought that the starch in the polished rice was toxic to the nerves, but he was wrong. Finally, Casimir Funk, a Polish chemist, showed that an extract of rice hulls prevented beriberi. He thought that this substance fell into the chemical category of “amines,” and since it was “vital” to life, he called it "vitamine." When the substance turned out not to be an amine, the ending “e” was dropped.
A short time later, E.V. McCollum and Marguerite Davis at the University of Wisconsin discovered that rats given lard as their only source of fat failed to grow and developed eye problems. When butterfat or an ether extract of egg yolk was added to the diet, growth resumed and the eye condition was corrected. McCollum suggested that whatever was present in the ether extract be called fat soluble “A,” and that the water extract Funk had used to prevent beriberi, be called water-soluble factor “B.” When the water-soluble extract was found to be a mixture of compounds, its components were given designations with numerical subscripts. The specific anti-beriberi factor was eventually called vitamin B1 or thiamine. These “vitamins” had a common function. They formed part of the various enzyme systems needed to metabolize proteins, carbohydrates and fats. Some of the compounds in Funk’s water extract eventually turned out to offer no protection against any specific disease and their names had to be removed from the list of vitamins. As other water soluble substances which were required by the body were discovered, they were added to the B vitamin list.
Update Week 2: Synthetic and Natural Vitamins
Many people wonder whether synthetic vitamins are identical to the natural version. Depends on which vitamin. Vitamin C, for example is the same compound whether synthesized in the lab or isolated from an orange. The situation is different for vitamin E. Back in the 1920s it was noted that the absence of a fat-soluble substance in the diet of rats led to sterility in males and the inability of females to carry their young to full term. This substance was named vitamin E, or "tocopherol," deriving from the Greek "tokos" for birth and "phero" to carry. Chemical analysis revealed that Vitamin E was actually composed of eight related compounds. These had differing abilities to prevent reproduction problems in rats, with "d-alpha-tocopherol" having the greatest biological activity. This substance was amenable to laboratory synthesis but when it was made in the lab it inevitably formed together with its non-identical mirror image form, "l-alpha-tocopherol," which did not exist in nature. The "l-isomer," as it was called, had far less biological activity than the "d."
Since the eight naturally occurring components of vitamin E and the synthetic "l" version all had different biological activities, there was a need for some standardized unit of measure for vitamin E activity. Weight would be misleading because 1 mg of synthetic vitamin E, which was composed of the active "d" and the less active "l" forms, would not have the same effect as 1 mg of pure "d." Therefore the term International Unit (IU) was defined to represent the biological activity of 1 mg of synthetic vitamin E. By this scale, d-alpha-tocopherol has an activity of 1.49 IU. Therefore any tablet labeled as having 200 IU of vitamin E, will have exactly the same ability to prevent reproductive problems in rats, although it may not have exactly the same composition as another tablet labeled 200 IU. "Natural" vitamin E tablets are generally made by extracting pure d-alpha-tocopherol from soybeans while the synthetic version consists of equal amounts of d-alpha-tocopherol and l-alpha-tocopherol. Neither contains any of the other seven components which are found in nature along with the d-alpha form.
Week 2 Update: Antioxidant disappointment
Recently more and more studies have come to the conclusion that outside of demonstrated nutritional deficiencies, vitamin and antioxidant supplements may be worse than useless. This possibility has now been underlined by a study carried out in Sweden in which researches administered either vitamin E or N-acetylcysteine, both antioxidants, to mice with early lung cancer. In doses comparable to those found in supplements, the antioxidants actually increased the number of tumours three fold in the experimental animals when compared with the controls. Furthermore, the tumours were more invasive and more aggressive and caused the supplemented animals to die sooner. Even more worrisome was the observation that in the laboratory the antioxidants accelerated the growth of cultured human lung cancer cells.
A possible explanation for the surprising detrimental effect of antioxidants observed in the original 1994 human study and in the recent rodent study is beginning to emerge. That explanation involves the well-known ability of cells to mount a defense against damage to the organism. Free radicals, as generated by smoking, exposure to ultraviolet light or by the cell’s use of oxygen can indeed damage DNA but cells are equipped with various enzymes that can repair the damage. And if the repair fails, a protein known as p53 triggers destruction of the cell before it can become malignant.
Apparently, antioxidants do indeed prevent some damage to DNA, but it seems that in this some prevention is worse than no prevention. That’s because the p53 protein only swings into action when a certain amount of DNA damage occurs. The theory is that antioxidants keep the damage at a level that prevents deployment of the p53 protein, allowing malignant cells to multiply. It must be remembered, though, that this was a study in mice with artificially induced lung cancer and that people are not giant mice. Still, it should serve to apply the brakes at least somewhat to the hype-oiled wheels of the rapidly rolling antioxidant bandwagon. However, given the massive amount of evidence about the benefits of vegetable and fruit intake, there is no reason to be concerned about their antioxidants content. Indeed, it may well be that these benefits have nothing to do with antioxidant activity.
Week 1, Lesson 4 Update:
Until recently vitamin D was promoted by some marketers for the prevention of cancer, cardiovascular disease and other conditions. The problem was that the rationale was mostly based on observational studies. In this type of study researchers follow a group of people to determine what factors may affect their health. But it is very difficult to draw conclusions from observational studies. It might be that people taking vitamin D are healthier, not because of the vitamin, but possibly because they have also a better diet or they exercise more. More conclusive data are based on randomized control trials. This involves following two groups of people, one group given vitamin D and the other a placebo, and looking for the outcome. In meta-analyses, studies are combined to increase the size of the pool and therefore reliability.
This is the approach followed by a group of New Zealand researchers. In “The Lancet Diabetes and Endocrinology (January 24, 2014),” they reported on meta-analyses of randomized controlled trials on skeletal, vascular and cancer outcomes associated with vitamin D supplementation. This involved examining 38 different trials with a total of over 80,000 different subjects.
The conclusion represents another setback for those who promote the routine use of vitamin supplements. There is little justification for prescribing vitamin D supplements in the general population to prevent cardiovascular disease, cancer, fracture, or to reduce the risk of death. Unfortunately I am not sure that the study will have an impact on supplement sales which in North America amount to more than $ 30 billion a year.
Week 1, COMMENT:
We founded the Office for Science and Society (OSS) in the fall of 1999 bringing Dr. Joe Schwarcz in as Director. I spent quite a bit of time sorting out the details of starting this adventure and a few years later, we were able to bring Dr. Ariel Fenster to McGill. Since then, I have not spent nearly as much time as Joe and Ariel in functioning in the Office due to my other involvements at McGill. Thus, the main credit to the successful functioning of the Office is credited to them. Shortly after the start of the OSS, a website was introduced.
In 2011, Dr. Lorne Trottier, endowed the OSS with some $5.5 million dollars to make possible the hiring of talented people like Ms. Emily Shore and Ms. Alexandra Pires-Menard who have greatly assisted in bringing the website to its present state. The site has grown significantly in the past 2-3 years and has expanded to one with a great many stories and features. It changes daily and my suggestion is that anyone in the MOOC course will keep quite up to date with various adventures about science by reading it regularly as this site focuses greatly on food issues. There is also a significant effort to expose dubious claims that regularly get made by charlatans and pseudo-science promoters like the Mighty Oz. Note the following article quoting “Dr. Joe” that was made recently in the Philadelphia Inquirer.
With the advent of our MOOC effort on Food, I have spent more time coordinating with the site and discovered that it clearly ranks with just about any science-based effort on the web. I hope to make more contributions to it in the coming years but at this time, the reason for this short piece is to give it my very strong endorsement as to how it meshes so very well with many of the goals of our MOOC course. Take a look!
Week 1, Lesson 3A:
MOOCing in Montreal
On the MOOC discussion board got wind of the fact that some people were organizing a Montreal "MOOC" meeting at Second Cup. Decided to drop in and had a fun discussion about the first lecture and other stuff...5 students today...10 next week..then 100.....who knows...... Contributed $8.50 to the Second Cup coffers for one hot chocolate and one latte. But the company was worth it.
Week 1, Lesson 3:
At the start of this presentation on scientific publishing, I spent some time talking about the food label for spinach where the “controversy” about the source of strength for the cartoon character “Popeye” was being described as to iron and vitamin A content. A great many countries have their own regulations as to the details of food labels. Canada differs somewhat from the FDA in the United States as to this practice however there is a general coherence with the two countries. Presently in the U.S., there are plans to change the size of the print on food labels (I guess for aging eyes) and to include a pie chart that would deliver a clear visual representation of the various ingredients. This is a welcome move as it is clear that the U.S. population (and many others even in the metric world) do not have a good understanding as to just how much a “gram” is. Even in metric Canada, most everyone still uses pounds when giving their weight. There is some discussion to include the rather arcane term (still in a great many cookbooks) “teaspoon” and “tablespoon” in order to help consumers. A recent survey estimated that about half of the overall population in the U.S. regularly read labels and nearly 60% of “older adults” do this, hence the need for larger type. Stay tuned- changes are afoot.
Week 1, Lesson 2:
As you will have seen in this presentation, McDonald’s has been the subject of some criticism about the nutritional value of its food offerings. However, the company’s reliability for consistent products from country to country is quite impressive. Whether it is in Europe or South Korea, McDonald’s is there with safe food in terms of microbial contamination. Netflix has a 20-minute film “Inside McDonald’s” (2013) that might give you some insights on this mega-company. According to the narration, they cater to nearly 70 million patrons a day in the world (118 countries- almost as many as we have represented in this course) and daily, about 8% of the population of the U.S.A. (25 million). Their statistics are impressive so take a look if you have time. They also feature a challenging interview with the CEO of the company.
Functional foods were discussed briefly as this is a growing area of business even encompassing the idea of putting vitamins and minerals into cola products. At McGill we were very pleased that several students in our Desautels School of Business managed to win a million dollar prize for proposing the use of insect protein as an emerging industry. We believe this will eventually catch on as a sustainable source of food, maybe in the future in the E.U. and North America. Approximately about 2 billion people world-wide regularly consume these creatures.
Week 1, Lesson 1:
The MOOC is off and running! One of the topics we discussed in the first lecture is the addition of calcium propionate to bread. This is a preservative that inhibits the growth of mould. It is a useful additive because moulds can produce a variety of nasty toxins. Like any other approved food additive, calcium propionate has had to pass a variety of safety tests before being allowed on the market. In this case that was not particularly difficult because propionates occur in the human body in copious amounts as products of fat metabolism. Indeed, our underarm secretions contain propionates. Could that explain why in France where propionates are not used the tradition is to carry baguettes under the arm? Another topic addressed was the enormous sugar content of soft drinks. A 350 mL can contains about 9 teaspoons of sugar! That may be surprising to some, but perhaps not as surprising as the fact that an equivalent amount of orange or apple juice contains the same amount of sugar. There was also a discussion of how advertisers sometimes overstep the boundries by promoting a product, pomegranate juice for example, as possessing special health properties that have not been scientifically proven.