Nutrition

Vitamin C

Question:

Is there any way to quantify the effects of vitamin c (or any other vitamin) on the human body without scientific equipment?

Answer:

On the whole, the chemicals we call vitamins are classified as such because they are involved in human metabolic processes that are impaired by a deficiency of the vitamin.

Because these agents act on normal human metabolism, the effects of the absence, presence or toxicity of the vitamin can usually be seen clinically. This means that there are signs and symptoms of deficiency, adequacy and toxicity that can be found by a person that knows what they are looking for. The scientific method is applied as the main tool to determine the general quantity of vitamin C in a person using the data collected by a clinician using their senses to detect abnormalities in the subject by history or on physical exam. In this sense, the clinician can quantify the presence of vitamin C as inadequate, adequate or toxic (or in other words “too little”, “enough” or “too much). Beyond the “too little”, “enough” or “too much” a scientist cannot detect a person’s vitamin C levels without chemical analysis. The actual concentration in terms of moles or grams of the agent in a sample (blood, urine, tissue) will require a chemical analysis using laboratory equipment (for vitamin C it is either through titration with a chemical reducing agent or via high performance liquid chromatography).

Specifically for vitamin C, deficiency leads to problems with collagen production and the development of scurvy with visible changes to the skin and gums. This would result in such things as: spongy gums, bleeding from mucosal surfaces (surfaces that line cavities in the body), skin spots and eventually open wounds and tooth loss. The relationship was discovered by Dr. James Lind in 1749. Vitamin C toxicity is harder to detect as the vitamin is not stored, is easily excreted and large doses are well tolerated. However very large doses can cause nausea and diarrhea. Large doses can also acidify the urine and change its colour.

Other vitamin deficiencies/toxicities are also detectable clinically through history and physical exam. Here are a few examples:

  1. Seizures in pyridoxine deficiency and neuropathy in toxicity
  2. Anemia and cardiac and neural tube defects in children of moms who were folate deficient at conception and during early pregnancy, anemia and cognitive dysfunction in B12 deficiency (which is rare due to recycling of the cobalamin portion of the vitamin and long-term storage)
  3. Rickets (boney prominences at growth plates in children) in vitamin D deficiency and nausea, anorexia, vomiting, polyuria, weakness, psychologic changes and eventual renal failure in vitamin D toxicity
  4. Various vision and skin effects from Vitamin A deficiency and toxicity.

Hope this helps,
- Julia Mills

 


 

Chocolate

Question:

In what food group does chocolate classify as?

Answer:

This is an excellent question! Chocolate is yummy and makes such a nice treat occasionally. But, because it’s high in fat and sugar, it isn’t part of any food group in Canada’s Food Guide. The Food Guide recommends to eat less often the foods and beverages high in calories, fat, sugars or salt such as cakes and pastries, chocolates and candies, cookies and ice cream, potato chips, soft drinks etc… . These foods are less healthy choices.

When you eat different foods from the Vegetables and Fruit, Grain Products, Milk and Alternatives, and Meat and Alternatives food groups it helps give you lots of energy to play! Eating different foods within each food group help you get all the vitamins and minerals you need. So, enjoy chocolate sometimes, and follow Canada’s Food Guide to help you stay healthy and strong!

If you want to know more about the Food Guide, I encourage you to visit the following website with your family: http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/index-eng.php

- Richard Hughson

 


 

Flavoured Water

Question:

I’m not a water drinker. The only water I drink in a day is what goes into my two coffees in the morning and what’s used to make Pepsi. Recently my daughter had me taste some orange-flavoured bottled water, and I have to say that I really liked it. But is it as healthy as unflavoured water? I would really like an answer to this question, because if it’s equally healthy I will definitely start drinking that throughout the day instead of Pepsi.

Answer:

Consuming any beverage will help you meet your daily water requirements, including fruit juices/drinks, soft drinks, milk, coffee, tea, and of course water (and flavoured water). About 80% of our daily water intake comes from beverages and up to 20% from food (especially high moisture foods like fruits and vegetables). While sensing thirst cues generally leads to drinking and easy quantification of fluid intake, as we age it may become more difficult to recognize thirst and remain hydrated. Because of the importance of maintaining water balance and its impact on the body’s normal physiological functioning, general guidelines from all sources for men and women aged 19 to 50 years recommend daily water intakes of 3.7L and 2.7L, respectively. However, these recommendations are only guidelines and you may require more or less depending on water losses from warmer temperatures and physical activity.

There are several factors that you should take into account to determine whether switching from cola to orange-flavoured water is right for you. First, consider the type of sweetener used in each beverage. The principal sweetener in most soft drinks is high-fructose corn syrup and/or a combination of glucose and fructose (these are the same sugars that occur naturally in fruits and vegetables). Orange-flavoured water usually includes some combination of natural fruit and low-calorie sweeteners: sucralose, aspartame, and acesulfame-potassium. Other than the difference in calories, none of these sweeteners, when consumed occasionally, pose any health problems to humans.

Second, because we tend to have an innate preference for sweet taste, both types of sweeteners will satisfy our “sweet tooth”. Once this appetite is fulfilled our desire for sweet-tasting products diminishes. As a result, over the course of a day, you may find it difficult to drink several servings of the same beverage. Rest assured, however, that both of these sweeteners are safe for human consumption, and when included in beverages will lead to meeting water requirements, satisfying sweet appetite, and quenching thirst.

Finally, the caffeine content is another consideration that may help you select an appropriate beverage. Soft drinks contain caffeine – a typical can of cola contains between 36 to 46 mg, and in general caffeine intake should not exceed 400 mg/day from all sources. You would have to consume eleven or more colas to exceed 400 mg of daily caffeine. Flavoured water does not contain any caffeine, and if you’re concerned about limiting your daily caffeine intake this may be another factor to consider when selecting the best beverage for you.

There remains considerable debate among nutritional scientists and healthcare professionals on whether the inclusion of these sweeteners in the diets of humans contributes to the development of obesity and metabolic disorders. The best available data suggests, however, that these beverages are fine when consumed in moderation as part of a balanced diet. Keep in mind that there are many beverages that are sources of water, and the key is to find something that you enjoy drinking in order to meet your body’s needs.

- Nick Bellissimo


Is there a difference between whole wheat and whole grain?

Question:

Is there a difference between whole wheat and whole grain? If so, which one is healthier?

Answer:

The difference between “whole wheat” products and “whole grain” products is the level of processing involved.

Grains in their whole form (e.g. barley, corn, oats, wheat, rice) are made up of three main components: the germ, the endosperm, and the bran. The germ is the embryo of the seed and is filled with B vitamins, vitamin E, and other micronutrients. The endosperm is the largest part of the grain, surrounding and providing energy to the germ. The endosperm is primarily made of starches, with some protein and B vitamins. The bran is the outer most layer and protects the grain; it contains dietary fibre, B vitamins, and other minerals.

“Whole grain” products have all three components (the endosperm, the bran, and the germ) in the same proportions as the intact grain. There is no bleaching or refining involved, but there may be other processing such as cracking, crushing, or cooking.

“Whole wheat flour” is similar to whole grain flour, however, some or much of the germ and bran is removed during processing. This means that whole wheat flour contains fewer nutrients than whole grain flour.

“White flour” is at the opposite end of the spectrum to whole grain flour, and is produced after grinding, milling, and separating the grains. The germ and bran are removed during the process, resulting in a flour/product that is basically just endosperm. Since white flour processing results in losing majority of the vitamins and minerals associated with the bran and germ, vitamins and minerals (e.g. niacin, thiamin, and B vitamins) are often added to the product, which is known as the “enrichment” process.

Due to the fibre and nutrient content of whole grains, Health Canada recommends that at least half of your grain products each day are whole grains.

- Nick Bellissimo


Is there a way to measure the amount of protein in eggs?

Question:

Is there a way to measure the amount of protein in eggs? If so how?

Answer:

Protein is one of three macronutrients that provide energy to our bodies. Proteins are made up of unique combinations of 20 different amino acid building blocks, giving each protein its specific structure and function. The amount of protein in the food and the types of amino acids in the protein can be most accurately assessed in a laboratory setting, for example:

  • Total protein concentration, also known as ‘crude protein content,’ can be assessed by measuring the nitrogen content of the food, since protein is the only macronutrient containing nitrogen. Food samples are heated or burned and from the end products, nitrogen content, and thereby the crude protein content of foods is determined. A common procedure employing these methods is called the Dumas method. Before the Dumas method was invented, for the past 100 years, crude protein content was measured using the Kjeldahl method. The Kjedahl method uses concentrated acid to slowly digest protein samples.
  • Protein composition (the types of protein) is assessed by separating and isolating individual proteins, based on their physical and/or chemical characteristics (e.g. size, charge, solubility). Eggs, for example, contain many different types of proteins. This means that each must be separated and measured in order to properly assess the protein composition of a food.

Since it is difficult to assess the amount of protein available in foods, the crude protein content is presented in the Nutrition Facts tables on food packages. Each food items nutrition table and information can also be found on the Canadian Nutrient File (CNF) website (https://food-nutrition.canada.ca/cnf-fce/index-eng.jsp). You can calculate the amount of macronutrients (including protein) using Nutrition Facts tables. For example, the CNF Nutrient Table shows that there are about 6.22g of protein in a large egg (approximately 53g). In 3 large eggs (approximately 159g), 18.66g of protein are present (6.22g/large egg x 3 large eggs).

- Nick Bellissimo


Determining the fat or cholesterol content of food

Question:

What is a suitable and simple experiment to test for levels of all the following substances/chemicals in oils: cholesterol, trans fat, saturated fat and unsaturated fat?

Answer:

Lipids are classified based on their structures. Fats are made up of fatty acids and a glycerol molecule. Saturated fatty acids make a straight-line chain, whereas unsaturated fatty acids have ‘kinks’ (from double bond(s) in the carbon chain) that cause a bend in the chain. [SIDE NOTE: The number of double bonds and location of double bonds are also used to further classify unsaturated fatty acids into monounsaturated (‘1 double bond’) and polyunsaturated (‘multiple double bonds’)]. Trans-fatty acids are type of unsaturated fatty acids, which have been partially hydrogenated– this can happen naturally or from food processing. A change in the double bond(s) structure takes place and the ‘kinks’ disappear, making it appear more like saturated fatty acids. Cholesterol, on the other hand, belongs to a different class of lipids than fatty acids known as sterols. Cholesterol is present in foods from animal sources and is also produced naturally by your body.

The best way to accurately determine trans-fatty acids, saturated fatty acids, unsaturated fatty acids, and cholesterol compositions in foods is through laboratory testing. A melting point test can determine the relative composition of saturated vs. unsaturated fatty acids. In addition, an iodine test (by adding iodine to a sample) can assess the presence of unsaturated fatty acids and the degree of saturation. When iodine solution (naturally brown) is added to a sample containing unsaturated fatty acids, the solution will become colourless. When the solution is added to a sample containing saturated fatty acids the solution will remain brown. The intensity of brown will indicate how much unsaturated fatty acids are present – the lighter the colour, the more unsaturated fatty acids are present. More complicated lab testing is done to look at cholesterol content.

Importantly however, the simplest way to know the fat or cholesterol content of foods is by reading the Nutrition Facts table on food packages, or using the Canadian Nutrient File website (https://food-nutrition.canada.ca/cnf-fce/index-eng.jsp).

- Nick Bellissimo

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