Over the course of the last several years, I’ve been conducting a study of human preferences. Admittedly, it’s a work in progress, and I’m careful not to describe it as a scientific investigation. Indeed, it’s just an observational exercise, but I am ready to offer a hypothesis.
There are exactly seven kinds of Homo sapiens extant in the USA. They may be labeled as Pinks, Greens, Yellows, Whites, Blues, Nones, and Anys. The distribution of these different members of our species is not uniform. There are regional, gender, age, political, and even religious factors that contribute to the behaviors that determine the exclusive membership in each group.
The distinctive behaviors can be observed around mealtimes, in homes and in restaurants. It can also be observed during shopping episodes in grocery stores, convenience stores, and other places where we might choose to satisfy our sweet tooth. Yes, I’m talking about how or if we choose to add something that tastes sweet to our food or drink.
What are you? And more importantly, why? That is the focus of my study. Please leave a comment describing your preference and the reasons for it. In a future essay I will share the results of my investigation.
My research has come to a satisfactory conclusion. These are the important findings.
- Sugar and its various substitutes are safe to eat in moderation for most people.
- Each of us is unique, and our diets should reflect our individual differences, tolerances, and preferences.
- Our preferences for food, and sweeteners, are often derived from magical or superstitious notions, and rarely from the sciences of nutrition and human physiology.
If you wish to read a brief but unbiased summary of the various sugar substitutes, I suggest FamilyDoctor.org, but even Wikipedia has some good information.
The reasons people give for choosing the pink, blue, green, white, yellow, or no packages to make their coffee or tea sweet are all over the map. Some use what their friends use. Some are influenced by advertising, negative or positive. Many are influenced by news reports of various studies, as well as various FaceBook postings favoring one over another. Quite a few base their choice on taste.
My obsession about the reasons we choose different sweeteners started when my wife and I went shopping in a Target store while traveling in California. We were staying in a nice resort north of San Diego on the coast and our suite included a nice kitchen, and most important of all, a coffee maker. We drink coffee in the morning and we needed to purchase the makings for our perfect brew. For me, that requires blue packages of Equal or one of the other brands with aspartame as the sugar substitute. To my amazement, that California Target did not stock any sweetener with aspartame. Every other sugar substitute on the market was present, Splenda, Stevia, Sweet & Low, and of course sugar. I asked a store employee and was told no one would buy it, so they stopped offering it. Back home it’s one of the most common sweeteners.
My formal education was in the sciences. Early in my career I taught several different college level general and organic chemistry courses, as well as other related disciplines. I studied biochemistry and human physiology in my graduate studies. Several of those courses were in the College of Medicine, although I was a graduate student not a medical student. Since completing my formal education, I continue to study in these areas of the sciences even after I left the classroom. I share this to illustrate that I know something about the ingredients of the various things we eat, and how they are metabolized.
Competition is brutal among the various companies that market sugar and its sweet substitutes. Advertising is rarely encumbered by the facts. It is impossible to make a wise decision about how to sweeten your tea or choose a sweet beverage to drink, if you rely upon advertising, posts shared on Facebook, and peer pressure. Apparently in Southern California, if you want to add Equal to your iced tea, you have to order it from Amazon, have it shipped in a non-descript package, and hide it from your friends.
Because I know what sugar and its sweet substitutes are and how they are metabolized, I’m fascinated by the different notions that people have about each of them. Again, I must stress they are all safe for most people, but each of us is unique. Allow me to describe each one starting with sugar.
Table Sugar (White) is actually sucrose. It is a disaccharide which means it is composed of two monosaccharides or simple sugars, glucose and fructose. Glucose is perhaps the most common organic molecular species found in nature. Starch and cellulose are comprised of glucose which is also known as dextrose. It is our fuel, our energy source. Many of the things we eat are converted to glucose for use by our muscles or stored as glycogen (short term) or fat (longer term) for future use. We cannot live without glucose.
Fructose, is the other monosaccharide in table sugar. It is not readily converted to glucose in the liver. If we eat too much sugar, most of us are unable to convert much of the fructose to glucose, and it is instead converted to liver fat, as well as fatty tissue in other organs such as the brain, kidneys, etc. Some people are fortunate to be able to handle the conversion better than others, and this is certainly related to lifestyle, age, and genetics. Fatty deposits in the liver and in other organs may lead to conditions such as fatty liver disease, metabolic syndrome, and others pathological conditions including Type II Diabetes. Until modern times, most human diets contained very little fructose, except in fibrous fruits and some vegetables where the absorption of fructose into the blood stream was slow and limited. Recent studies indicate that high concentrations of fructose in the bloodstream may cause an inflammatory response in arterial walls, as well as cardiac and other vascular tissue rendering them sticky to lipoproteins and other molecules transported in the blood. For most of us, sugar should be eaten in moderation and best eaten in fruits not from little white packages.
Sucralose (Splenda – Yellow) is a derivative of sucrose made by substituting chlorine atoms for hydroxyl groups on the disaccharide molecule. The result is a substance which is as much as 700 times sweeter than sucrose, meaning that very little is ingested when it is used to sweeten beverages or other foods. It passes through the digestive system without entering the bloodstream and therefore does not provide energy. It is a zero calorie synthetic sugar substitute. It is useful in food preparation because it does not break down when it is cooked retaining its sweetness. Recent studies raise questions about the effect that sucralose might have on the intestinal micro biome (gut bacteria). Since it is a relatively stable chlorinated hydrocarbon derivative, there are also concerns about its persistence in the environment and in sewage treatment. Fortunately, due to its extreme sweetness very little is actually ingested or subsequently delivered into the biosphere. The FDA suggests limiting the daily ingestion of sucralose to not more than 9 mg/kg of body mass. More studies are needed about this sweetener usually offered in yellow packages.
Saccharin (Sweet & Low – Pink) has been used as a synthetic sugar substitute for a very long time, over a hundred years. It was discovered in 1879 and has been approved as a food additive since 1912 without any known adverse effects. The less formal chemical name is benzoic sulfimide, and it may be about 400 times sweeter than table sugar but this varies depending upon its formulation. It’s safety as a sugar substitute has been demonstrated over a long period of use, but recent studies also call into question its impact on the bacterial environment of the gut. It has an unpleasant metallic or bitter aftertaste which is why it is often mixed with glucose and other sweeteners to mask the effect. The official Acceptable Daily Intake of Saccharin is 5 mg/kg of body mass.
Stevia (Green) is a mixture of steviol glycoside compounds extracted from plants of the species Stevia rebaudiana. This sweetener has been in common use in Japan for many years. Certain of the glycosides received approval in the United States in 2008 and Europe in 2011, and are sold as Truvia by Cargill and Coca Cola, and PureVia by PepsiCo. The plant extract was originally banned in the Unted States in the early 1990’s because of carcinogenic fears later alleviated through testing and subsequent restrictions to specific glycosides present in the plant extract. Stevia sweetener is a non-caloric additive because it passes through the digestive system and into the intestine where it is metabolized by bacteria without the glucose or steviol entering the blood stream. The micro biome of the gut is definitely affected, but apparently without adverse effects. The green package and marketing as a “natural” sweetener have helped promote its use, but the FDA approval is limited to daily ingestion of 4 mg/kg of body mass because of concerns about its safety, less than half the recommended limit for sucralose and the lowest recommended daily intake of all. Certainly, not all “natural” plant extracts are safe, in fact some are deadly, and green is just one of the colors of the rainbow.
Aspartame (Equal – Blue) is the methyl ester of a dipeptide of the naturally occurring amino acids aspartic acid and phenylalanine, and therefore, the only sugar substitute with an entirely natural composition. Virtually all proteins contain these two amino acids and they are present in most cells in our bodies. Phenylalanine is an essential amino acid, meaning it is one of the eight that must be included in our diets because we lack the biochemical pathways to make them ourselves. Aspartic acid is among the most common amino acids in natural proteins. It is just about impossible for a human to avoid eating foods with protein containing aspartic acid, phenylalanine, and the methyl ester functional group in quantities much larger than when ingesting aspartame as a sugar substitute. It is about 200 times as sweet as sugar, and the official Acceptable Daily Intake is 50 mg/kg of body mass, or at least ten times safer than other sugar substitutes and sugar itself. When ingested, it is hydrolyzed to the two naturally occurring amino acids which are absorbed into the blood stream as are other amino acids from the digestion of protein. These metabolites are then available for various metabolic pathways involving the amino acids such as the making of proteins and enzymes essential for our health. Like the other sugar substitutes mentioned above, aspartame is very much sweeter than sugar, and that is why it has almost no calories. The amount present in a blue package of Equal is so small that it is almost not visible. Most of what you see in that blue package is glucose and a starch derivative added for packaging purposes only. The downside of aspartame is its relatively short shelf-life. If you heat it, it breaks down to the two amino acids which have no sweet taste. This also happens over time which explains the expiration dates on containers of foods and drinks sweetened with aspartame.
There is a warning label on all foods and beverages that include aspartame. The warning is related to the essential amino acid phenylalanine. Individuals with the extremely rare genetic condition known as PKU Syndrome must follow special diets that restrict the intake of this amino acid because of the absence of an enzyme that metabolizes tryptophan, which we make from phenylalanine. Too much phenylalanine in the diets of these people can lead to the toxic buildup of tryptophan with harmful consequences. All babies born in the USA and most developed countries are tested for PKU at birth. Only 1 in 10,000 infants test positive for PKU.
Aspartame has been the victim of numerous internet hoaxes. It is one of the most studied food additives by the FDA, and no harmful effects have ever been shown in legitimate scientific research. This is really not surprising when you know what it is. Aspartic acid and phenylalanine are already in our diets in the proteins we eat, and so is the methyl ester functional group (one glass of wine or beer contains far more than a twelve pack of diet soda).
Other sugar substitutes such as the sugar alcohols and acesulfame are also used alone and in combination with the above to sweeten our foods and beverages. Again, they are generally safe in moderation. Acesulfame, also known as Ace-K, is usually found in combination with saccharin and other sweeteners to mask the aftertaste. The recommended daily intake is 15 mg/kg of body mass.
Sugar alcohols are not sugars, thereby adding to our confusion. A sugar is defined as a poly-hydroxyl aldehyde or ketone, and since sugar alcohols lack the aldehyde or ketone functional group, they don’t have to be listed as sugars on the label. It is a marketing game. These substances are not zero calorie sweeteners. Additionally, the bacteria in our guts metabolize them causing some gas and other discomforts in people who eat foods containing large quantities, especially sugar-free candies and cookies among others.
Conclusion: Whether you choose pink, yellow, white, blue, or green packages to sweeten your beverages, you are generally safe if used in moderation. Beware of packaging and labeling, natural doesn’t always mean natural, and sugar free doesn’t always mean low calorie. Green and yellow are not necessarily good for you or the environment. Just because your grandmother only used white packages doesn’t mean you should. If you live in California, you might have to hunt for blue, because Donald Rumsfeld once served as CEO of S.B Searle and Company.
By every measure and scientific study, aspartame is the safest and nutritionally best for you to use to sweeten your food or drink. For most of us who aren’t 16 year old athletes, sugar is probably the least healthy. But again, we are each unique, and of these sweeteners are safe in moderation.