Matteo Tino, B. Kin, PTS, CSCS
Vitamin D is prevalent in a limited number of foods such as fatty fish (i.e. Salmon), egg yolks and milk. It is important in the regulation of phosphorus and calcium in the blood. (DeLuca, 1993) Vitamin D is also produced in the skin by UVB radiation (sunlight). However, most milk is not fortified with enough Vitamin D to act as an appropriate supplement, and most North Americans do not receive enough sunlight to meet their daily vitamin D requirements. (Zella, McCary, & DeLuca, 2003). Ideal consumption of vitamin D is about 20µg (µg=micrograms) or 800IU (UI=International Units) per day; although, this number may be too low. (Veith, 2004) In the absence of sunlight at least 25µg (1000 IU) of Vitamin D is required. (Veith, 2004) Vitamin D deficiency has already been associated with rickets and vitamin D is effective in the prevention of osteoporosis, heart disease and some cancers. (Holick, 2004) Recent research has begun to show a correlation between vitamin D consumption and a decreased risk of type 1 (insulin-dependent) diabetes. Diabetes is a major cause of blindness, amputation and death in North America; and between the years 1995-2025 there will be a 35% increase in the world prevalence of diabetes. (King, Aubert & Herman, 1998) As well, there is epidemiological research that shows a relationship between a lack of sun exposure and the risk of diabetes. (Dahlquist & Mustonen, 1994)
According to three separate studies (see Research Review below) a relationship exists between vitamin D consumption and the prevention of type I diabetes. Vitamin D consumption and supplementation is an effective way to prevent the onset of type 1 diabetes. More specifically, a daily 50µg (2000IU) dose of vitamin D greatly reduces the risk of type 1 diabetes in children; and vitamin D supplementation is effective in preventing type 1 diabetes, especially in the absence of appropriate UVB radiation.
Although there are obvious health benefits to the consumption of Vitamin D, there may also be many health risks associated with the over-consumption of vitamin D. Vitamin D “supplementation is only beneficial and safe when the person’s biological concentration of the vitamin is less than optimal.” (Hypponen, Laara, Reunanen, Jarvelin & Virtane, 2001) The Upper Limit (UL) is the maximum amount of a nutrient that a majority of the population can consume before there are health risks. The UL for Vitamin D is 50µg (2000IU) per day (Munro, 2001). However, according to one study, 78% of children who consumed at least 2000IU of Vitamin D had a reduced risk of Type 1 Diabetes. (Hypponen, Laara, Reunanen, Jarvelin & Virtane, 2001). Regardless, Vitamin D supplementation is not effective if it leads to other diseases due to over-supplementation. Also, the relationship between vitamin D consumption, calcium absorption and diabetes should be examined. The benefits of vitamin D consumption may be due to the increased absorbance of calcium. As well, there are many associated risks with exposure to UVB radiation. Sunlight is effective in producing vitamin D in the skin, however increased unprotected exposure to the sun may lead to sun stroke, dehydration, burning and, in some cases, cancers.
Although vitamin D supplementation is effecting in warding off type 1 diabetes, other factors such as diet, body composition and activity level need to be considered. Parents need to be conscious of what their children are eating and how active their children are. An inactive child with poor eating habits is still at risk of developing diabetes regardless of vitamin D supplementation.
Research Review
Intake of Vitamin D and the risks of type 1 diabetes: A birth-cohort study
Hypponen, E., Laara, E,. Reunanen, A., Jarvelin, M.R. & Virtane, S.M.
This study examined the possible relationship between early childhood vitamin D consumption and the risk of type 1 diabetes. The experimenters expected to see a negative relationship between the consumption of vitamin D and the prevalence of type 1 diabetes. A total of 10 821 children participated in the study. Children who regularly supplemented for vitamin D had an 88% decrease in Type 1 diabetes risk when compared to children who did not supplement for vitamin D. Children that consumed 50µg (2000IU), the recommended daily dose of vitamin D, had a 78% reduction in type 1 diabetes risk than children who received a lower dosage. Essentially, consuming 2000IU of vitamin D daily in the first year of life lowers the risk of type 1 diabetes.
Vitamin D supplement in early childhood and risks for type 1 (insulin-dependent) diabetes mellitus
The EURODIAB Substudy 2 Study Group
The aim of this study is to determine whether there is a relationship between early childhood vitamin D consumption and the risk of type 1 diabetes for several populations across Europe. The authors hypothesized that “non-genetic risk factors which can trigger the events subsequently leading to childhood-onset diabetes are operating early in life”, and that vitamin D supplementation is effective in the prevention of type 1 diabetes. The study concludes that vitamin D supplementation leads to a decreased risk of child-onset type 1 diabetes.
Oral administration of 1,25-dihydroxyvitamin D3 completely protects NOD mice from insulin-dependent diabetes mellitus
Zella, J.B., McCary, L.C. & DeLuca, H.F.
The aim of this experiment was to determine the effectiveness of vitamin D in the prevention of type 1 diabetes in non-obese diabetic mice. The experimenters hypothesized that vitamin D supplementation from UV radiation and oral supplementation will protect the mice from type 1 diabetes. 65% of vitamin D deficient mice who received no vitamin D supplementation were diabetic compared to only 26% of vitamin D sufficient mice who only received UV radiation. In addition, vitamin D deficient mice had an earlier onset of diabetes than the vitamin D sufficient mice. Mice that received a daily 50ng oral supplement of vitamin D had no incidence of type 1 diabetes, whether they received UV radiation or not. This study shows the strong relationship between vitamin D supplementation and the decreased risk of type 1 diabetes, especially in the absence of UVB radiation.
References
Dahlquist, G. & Mustonen, L. (1994). Childhood onset diabetes - time trends an
climatological factors. International Journal Epidemiology, 23, 1239-1241
DeLuca, H.F. (1993). Vitamin D: 1993. Nutrition Today, 28, 6-11.
Holick, M.F. (2004). Vitamin D: importance in the prevention of cancers, type 1 diabetes,
heart disease, and osteoporosis. American Journal of Clinical Nutrition, 79, 362-371.
Hypponen, E., Laara, E,. Reunanen, A., Jarvelin, M.R. & Virtane, S.M. (2001). Intake of
vitamin D and risk of type 1 diabetes: A birth-cohort study. The Lancet, 358, 1500-1503.
King, H., Aubert, R.E. & Herman, W.H. (1998). Global burden of diabetes, 1995-2025:
Prevalence, numerical estimates, and projections. Diabetes Car, 21(9), 1414-1431.
Munro, I. (2001). Derivation of tolerable upper intake levels of nutrients. American
Journal of Clinical Nutrition, 74, 865-867.
The EURODIAB Substudy 2 Study Group. (1999).Vitamin D supplement in early
childhood and risk for type I (insulin-dependent) diabetes mellitus. Diabetologia,
42, 51-54.
Vieth, R.(2004). Why the optimal requirement for Vitamin D3 is probably much
higher than what is officially recommended for adults. Journal of Steroid Biochemistry & Molecular Biology 89–90, 575–579
Zella, J.B., McCary, L.C. & DeLuca, H.F. (2003). Oral administration of 1,25-
dihydroxyvitamin D3 completely protects NOD mice from insulin-dependent diabetes mellitus. Archives of Biochemistry and Biophysics, 417, 77–80
May 26, 2006
Everything You Ever Wanted to Know About Fiber (But Were Too Afraid to Ask)
By: Matteo Tino, B. Kin, PTS, CSCS
“What is fiber?”
Essentially, fiber (or dietary fiber) refers to plant materials which cannot be digested by the stomach and small intestines of humans. Fiber is typically divided into two groups based on physical characteristics: Soluble (dissolve in water or absorb water) and Insoluble (do not dissolve in water); however, in the near future, insoluble and soluble may no longer be used to describe fiber types. Instead, fiber may be classified based on its physiologic effects (Salvin, 2005). Most foods of plant origin contain a mixture of both fibers.
“Why is fiber good for me?”
Fiber assists with a number of bodily functions including regularity and reduction of blood cholesterol. Fiber consumption has a positive effect on weight loss and preventing weight gain. (Salvin, 2005) As one observational study on fiber consumption and weight loss concluded: “Regardless of fat intake, participants who consumed the most fiber gained less weight compared with individuals who consumed the least amount of fiber (Salvin, 2005).” As well, “populations that report higher fiber consumption also demonstrate lower obesity rates (Salvin, 2005).” Other proposed benefits of dietary fiber consumption are listed in Figure 1.
Figure 1: benefits of dietary fiber consumption (adapted from Salvin, 2005)
“How much fiber should I be eating?”
Current recommendations for fiber intake are 38 g/d (grams per day) for men and 25 g/d for women (Salvin, 2005). You can also calculate fiber requirements using caloric intake: individuals should consume 10 to 13g of fiber per 1000kcal (or Calories) consumed. Table 1 provides an easy reference for fiber intake. Foods high in fiber include most fruits, vegetables, whole grains and beans/legumes. Although a diet that meets the recommendation for fiber intake has many benefits, too much fiber can decrease the energy density of the diet, reduce nutrient absorption, and if the diet is not adequate in fluid, cause constipation. (Grosvenor & Smolin, 2002)” Thus, if you are consuming a high fiber diet make sure to drink plenty of water.
(Salvin, 2005)
Some tips for increasing fiber intake:
Ø Eat whole fruits instead of drinking fruit juices.
Ø Replace white rice, bread, and pasta with brown rice and whole-grain products.
Ø Choose whole-grain cereals for breakfast.
Ø Snack on raw vegetables instead of chips, crackers, or chocolate bars.
Ø Substitute legumes for meat two to three times per week in chili and soups.
Ø Experiment with international dishes (such as Indian or Middle Eastern) that use whole grains and legumes as part of the main meal (as in Indian dahls) or in salads (for example, tabbouleh)
(http://www.hsph.harvard.edu/nutritionsource/fiber.html)
“I am on low-carbohydrate diet. Am I getting enough fiber?”
The answer is: probably not. Studies of the most popular high protein, low carbohydrate diets show insufficient dietary fiber content. Diets such as the Zone and Protein Power have fiber intakes of 18.1 g (consuming 1600kcal/day) and 10.6g respectively (Salvin, 2005). Two of the most popular low-carb diets today are Atkins and the South Beach Diet (Salvin, 2005). Both diets are described as being extremely low in dietary fiber (Table 2) - less than 10g/d! If you are on a carbohydrate restrictive diet you should ensure that you are consuming enough fiber through fruits, vegetables, beans/legumes, nuts, seeds, whole grains (bran) and/or supplementation.
(Salvin, 2005)
“Which Foods are high in fiber?”
In general most fruits, vegetables, nuts, seeds, whole grains (bran) and beans/legumes are relatively high in fiber. The website below contains a list of some popular food items and their fiber content.
http://www.fatfreekitchen.com/fiberlist.html
For more information visit: http://www.hsph.harvard.edu/nutritionsource/fiber.html
References:
Slavin, JL. Dietary fiber and body weight. Nutrition 21 (2005) 411-418
Grosvenor, MB. & Smolin, LA. Nutrition: From Science to Life. Toronto: Harcourt Publishing, 2002.
“What is fiber?”
Essentially, fiber (or dietary fiber) refers to plant materials which cannot be digested by the stomach and small intestines of humans. Fiber is typically divided into two groups based on physical characteristics: Soluble (dissolve in water or absorb water) and Insoluble (do not dissolve in water); however, in the near future, insoluble and soluble may no longer be used to describe fiber types. Instead, fiber may be classified based on its physiologic effects (Salvin, 2005). Most foods of plant origin contain a mixture of both fibers.
“Why is fiber good for me?”
Fiber assists with a number of bodily functions including regularity and reduction of blood cholesterol. Fiber consumption has a positive effect on weight loss and preventing weight gain. (Salvin, 2005) As one observational study on fiber consumption and weight loss concluded: “Regardless of fat intake, participants who consumed the most fiber gained less weight compared with individuals who consumed the least amount of fiber (Salvin, 2005).” As well, “populations that report higher fiber consumption also demonstrate lower obesity rates (Salvin, 2005).” Other proposed benefits of dietary fiber consumption are listed in Figure 1.
Figure 1: benefits of dietary fiber consumption (adapted from Salvin, 2005)
“How much fiber should I be eating?”
Current recommendations for fiber intake are 38 g/d (grams per day) for men and 25 g/d for women (Salvin, 2005). You can also calculate fiber requirements using caloric intake: individuals should consume 10 to 13g of fiber per 1000kcal (or Calories) consumed. Table 1 provides an easy reference for fiber intake. Foods high in fiber include most fruits, vegetables, whole grains and beans/legumes. Although a diet that meets the recommendation for fiber intake has many benefits, too much fiber can decrease the energy density of the diet, reduce nutrient absorption, and if the diet is not adequate in fluid, cause constipation. (Grosvenor & Smolin, 2002)” Thus, if you are consuming a high fiber diet make sure to drink plenty of water.
(Salvin, 2005)
Some tips for increasing fiber intake:
Ø Eat whole fruits instead of drinking fruit juices.
Ø Replace white rice, bread, and pasta with brown rice and whole-grain products.
Ø Choose whole-grain cereals for breakfast.
Ø Snack on raw vegetables instead of chips, crackers, or chocolate bars.
Ø Substitute legumes for meat two to three times per week in chili and soups.
Ø Experiment with international dishes (such as Indian or Middle Eastern) that use whole grains and legumes as part of the main meal (as in Indian dahls) or in salads (for example, tabbouleh)
(http://www.hsph.harvard.edu/nutritionsource/fiber.html)
“I am on low-carbohydrate diet. Am I getting enough fiber?”
The answer is: probably not. Studies of the most popular high protein, low carbohydrate diets show insufficient dietary fiber content. Diets such as the Zone and Protein Power have fiber intakes of 18.1 g (consuming 1600kcal/day) and 10.6g respectively (Salvin, 2005). Two of the most popular low-carb diets today are Atkins and the South Beach Diet (Salvin, 2005). Both diets are described as being extremely low in dietary fiber (Table 2) - less than 10g/d! If you are on a carbohydrate restrictive diet you should ensure that you are consuming enough fiber through fruits, vegetables, beans/legumes, nuts, seeds, whole grains (bran) and/or supplementation.
(Salvin, 2005)“Which Foods are high in fiber?”
In general most fruits, vegetables, nuts, seeds, whole grains (bran) and beans/legumes are relatively high in fiber. The website below contains a list of some popular food items and their fiber content.
http://www.fatfreekitchen.com/fiberlist.html
For more information visit: http://www.hsph.harvard.edu/nutritionsource/fiber.html
References:
Slavin, JL. Dietary fiber and body weight. Nutrition 21 (2005) 411-418
Grosvenor, MB. & Smolin, LA. Nutrition: From Science to Life. Toronto: Harcourt Publishing, 2002.
Breast Cancer Survivors and Exercise
Breast Cancer Survivors and Exercise: A Research Summary
Matteo Tino, B. Kin, PTS, CSCS
Prolonged inactivity during and post breast cancer treatment may have many negative consequences, including “reduced ability to tolerate active daily living and recreational pursuits, as well as impaired psychological well being (Cheema & Gaul, 2006).” In addition, weight gain experienced during treatment has many adverse side effects such as obesity, cardiovascular disease, diabetes and an increased risk of disease reoccurrence.
In an article published in The Journal of Strength and Conditioning Research researchers from Canada and Australia found that exercise has positive benefits in post operative breast cancer survivors with prior upper body aerobic training experience.
27 subjects of variable age (45-70yrs) and post treatment time (9m-21yrs) participated in weight training two (2) times per week and anaerobic conditioning three (3) times per week. The subjects completed full body weight training programs consisting of ten exercises (Table 1) at 8-12 repetitions each (with the exception of abdominal work, which was completed to exhaustion). “Subject alternated upper- and lower-body exercises, and rested approximately 2 minutes between sets (Cheema & Gaul, 2006).” Aerobic training involved self selected activities performed at 65-85% of the participant’s maximum heart rate. (Table 2) A warm-up and dynamic stretching was performed before exercise, and static stretching was performed after each exercise session
TABLE 1. The number of sets of each 8–12RM resistance training exercise prescribed per resistance training session by training week
(Cheema & Gaul, 2006)
TABLE 2. Prescribed time spent in the target heart rate zone per aerobic training session by raining week (Cheema & Gaul, 2006)
After eight weeks of training subjects had significant increases in upper- and lower-body strength and endurance, flexibility and overall Quality of Life when compared to their pretest levels. A decrease in waist and hip girth with no significant changes in body weight was also observed
Previously, it was thought that postoperative intense exercise will result in Lymphedema (A condition in which excess fluid collects in tissue and causes swelling. It may occur in the arm or leg after lymph vessels or lymph nodes in the underarm or groin are removed or treated with radiation.). Exercise may help to make the body more efficient in preventing this condition.
“This research is the first to demonstrate that survivors of breast cancer can safely perform upper-body resistance training at an intensity equal to that recommended for the general population (Cheema & Gaul, 2006).”
Reference
Cheema, BS & Gaul, CA. Full-body exercise training improves fitness and quality of life in survivors of breast cancer. J Strength Cond Res. 2006 Feb;20(1):14-21.
Always speak with your doctor before beginning any exercise program.
Matteo Tino, B. Kin, PTS, CSCS
Prolonged inactivity during and post breast cancer treatment may have many negative consequences, including “reduced ability to tolerate active daily living and recreational pursuits, as well as impaired psychological well being (Cheema & Gaul, 2006).” In addition, weight gain experienced during treatment has many adverse side effects such as obesity, cardiovascular disease, diabetes and an increased risk of disease reoccurrence.
In an article published in The Journal of Strength and Conditioning Research researchers from Canada and Australia found that exercise has positive benefits in post operative breast cancer survivors with prior upper body aerobic training experience.
27 subjects of variable age (45-70yrs) and post treatment time (9m-21yrs) participated in weight training two (2) times per week and anaerobic conditioning three (3) times per week. The subjects completed full body weight training programs consisting of ten exercises (Table 1) at 8-12 repetitions each (with the exception of abdominal work, which was completed to exhaustion). “Subject alternated upper- and lower-body exercises, and rested approximately 2 minutes between sets (Cheema & Gaul, 2006).” Aerobic training involved self selected activities performed at 65-85% of the participant’s maximum heart rate. (Table 2) A warm-up and dynamic stretching was performed before exercise, and static stretching was performed after each exercise session
TABLE 1. The number of sets of each 8–12RM resistance training exercise prescribed per resistance training session by training week
(Cheema & Gaul, 2006)
TABLE 2. Prescribed time spent in the target heart rate zone per aerobic training session by raining week (Cheema & Gaul, 2006)
After eight weeks of training subjects had significant increases in upper- and lower-body strength and endurance, flexibility and overall Quality of Life when compared to their pretest levels. A decrease in waist and hip girth with no significant changes in body weight was also observed
Previously, it was thought that postoperative intense exercise will result in Lymphedema (A condition in which excess fluid collects in tissue and causes swelling. It may occur in the arm or leg after lymph vessels or lymph nodes in the underarm or groin are removed or treated with radiation.). Exercise may help to make the body more efficient in preventing this condition.
“This research is the first to demonstrate that survivors of breast cancer can safely perform upper-body resistance training at an intensity equal to that recommended for the general population (Cheema & Gaul, 2006).”
Reference
Cheema, BS & Gaul, CA. Full-body exercise training improves fitness and quality of life in survivors of breast cancer. J Strength Cond Res. 2006 Feb;20(1):14-21.
Always speak with your doctor before beginning any exercise program.
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