By Leif Simmatis
The human body is imperfect. This is a statement that most people could probably agree with from firsthand experience; how else can we describe our susceptibility to physical injury or our dependency on synthetic medications.
Imperfection leads to incompletion. That is to say that, in all of our necessary complex bodily processes, there are key factors still missing. The human body requires certain organic substances to perform many everyday reactions. These substances are called vitamins.
Vitamins rarely cross our minds, which is interesting considering how vital they are to our survival. Luckily, we live in an age where most of the thinking regarding vitamins is already done for us. Deficiencies are uncommon because of varied diets and foods that are artificially fortified to provide us with many of the vitamins that we need.
Vitamins all play vital roles in metabolism (the word vitamin is derived from the term vital amine) and can be subdivided into two main groups: the fat-soluble vitamins (A, D, E and K) and the water-soluble vitamins (C and B complex).
Water-soluble vitamins are those that can, as their name would suggest, be dissolved in water and watery foods. This means that, although they are easily obtained, they are also rapidly removed from the body and so need to be replaced at least semi-regularly.
Fat-soluble vitamins are quite functionally distinct from the water-soluble vitamins, mainly for the reason that they are stored in tissues for much longer. This is because they are not excreted as rapidly. That being said, there are still many rich dietary sources for the fat-soluble vitamins (with the exception of D). Fatty fish, for example, as well as liver and carrots, are rich sources of vitamin A (although liver is also high in B vitamins).
Vitamin C, scientific alias ascorbic acid, is a popular vitamin. It’s the one that everyone knows to get from drinking a glass of orange juice or eating colourful vegetables. It has a wide range of roles in the human body. Vitamin C functions in antioxidant defense, collagen synthesis (creation), neurotransmitter synthesis and immune responses It is so imperative, that most animals have the ability to internally synthesize it themselves. Unfortunately, humans (along with chimps and guinea pigs) don’t carry this trait.
Vitamin C’s popularity may have stemmed from its role in the prevention of scurvy, a disease that used to be widely contracted by sailors. Sailors lived without fresh fruits and vegetables for months at a time, which led to a deficiency in Vitamin C. We now know that the symptoms of scurvy — bleeding gums, hair loss and skin flaking — developed from the inability to synthesize collagen properly. Thankfully for those poor sailors en route to the New World, Native Americans provided them with cedar bark tea which contains vitamin C and helped cure them. The reason for the sailors’ deficiency boils down to (sorry, tea pun) the fact that vitamin C is water-soluble and so it is not effectively stored by the body. Thus, it must be taken in semi-regularly.
The B-vitamins are other such entities. They all function in chemically similar ways, and so they have been given numbers that reflect this organization. There are a dozen or so, B1 through B12, which go by various names: riboflavin (B2), niacin (B3), folate (B9) and even more complicated ones such as pyridoxine (B6) and cobalamin (B12), so called because it contains cobalt, which is quite unique indeed. They are needed for many aspects of energy metabolism and for the synthesis of different cell types. Most B-vitamins are easily obtained from eating vegetables; however, vitamin B12 is only found in meat, fish and dairy because animals have the intestinal bacteria that creates it. This commonly causes a vitamin B12 deficiency in vegans and vegetarians. However, the B-vitamins are also artificially supplemented in many foods, such as cereal. The B-vitamins are primarily co-enzymes; that is, enzymes use them within our bodies in order to function. Vitamins B6 and B12 are primarily involved in the conversion of food into cellular energy, and for this reason, a deficiency in vitamin B6 and vitamin B12 is characterized by a lack of energy.
“You have a three-year supply of vitamin B12 in your liver,” Dr. Glenville Jones, professor in the Department of Biomedical and Molecular Sciences (DBMS), said in an interview. He continued to say that, with the exception of vegetarians or people on other restrictive diets, vitamin supplements are not needed. And not just in the case of the B-vitamins.
“There is a limited need for one-a-days,” Dr. Jones said. “The focus should be on a balanced diet instead [of on supplements].”
Dr. Jones’ research primarily focuses on the fat-soluble vitamins A and D.
Vitamin A, also known as retinol, is needed for embryological development and, as the scientific name would imply (think “retina”), for vision. However, vitamin A is also associated with a great degree of toxicity if overdosed. Ingestion of over 4000 IU (1200 micrograms) per day per kilogram of body weight can lead to the development of symptoms over the course of six months. The fluid around the brain can swell and liver damage can occur. In fact, there are anecdotes that Inuit peoples avoid eating the liver in bears and seals because it makes them sick (supposedly due to the high concentration of vitamin A in the liver). As well, there are stories of desperate Arctic explorers consuming entire animals that they kill, including the liver, and then becoming dazed due to toxic effects and eventually dying.
Vitamin D, on the other hand, is actually quite difficult to attain from the diet alone; overdoses are very rare. Vitamin D is primarily in fatty fish, such as sardines and salmon, and there are reports of a Norwegian “vitamin D booster meal” composed mainly of D-rich foods, eaten all at once. Aside from this extreme instance, though, vitamin D is relatively hard to come by.
“You can count on one hand the number of [well-investigated] cases of vitamin D overdose,” Dr. Jones said. “In Poland, I gave a talk on a certain disease which prevents the breakdown of vitamin D, which affects around one in fifty thousand.” This, he adds, is one of the few ways to experience potential vitamin D overdose.
Vitamin D is synthesized naturally in our bodies in response to sunlight. However, this means that at our latitude in Canada we are unable to make it between the months of October and April. This is due to inadequate UVB ray exposure; UVB rays breakdown are required for the breakdown vitamin of D’s precursor molecule.
Vitamin D is needed for the proper formation of bones and its deficiency is implicated in Rickets Disease. In the 1960’s Charles Scriver, a Quebec physician, pushed for Quebec’s dairy products to be fortified with vitamin D. After he succeeded, the number of annual cases of Rickets dropped from 120 to under 10.
Now many of our foods are fortified with both vitamins A and D (fat-soluble), even ones that would seem counterintuitive. Take, for example, water-based orange juice; in this case the fat-soluble vitamins are emulsified using starches, which suspend them in their watery environment. This is why some drinks are supposed to be shaken before drinking. Although after a while the water-soluble coating on the fat-soluble vitamins will eventually break down and the substance inside will get oxidized by the water.
With the recent opening of a pharmacy on campus, the point is raised: do we really need vitamin supplements?
“There is a lot of misinformation,” Dr. Jones said. “Most people likely don’t have a problem, but rather see taking vitamin supplements as an insurance policy.” This returns to the point that many of our foods are heavily artificially fortified or, in the case of vegetables and fruits, naturally fortified. For example, whole grain bread would be richer in the B vitamins than white bread, except white bread manufacturers now add all of the B-vitamins back in post-processing.
The bottom line: should you shell out for those C-boosters, or just eat a salad? Personally, the lush layer of leafs wins every time.
Dr. Glenville Jones specializes in the fat-soluble vitamins A and D on which he has published chapters in the Cambridge World History of Food, as well as the Canadian version of Dietary Reference Intakes, which is used by Health Canada to recommend daily intake levels for vitamins.