Ch10 Bone Health


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  • Figure 10.6
  • Kyphosis from page 376
  • Figure 10.8
  • Figure 10.12
  • Figure 10.10
  • Page 387 – think there may be a typo/confusing wording in this sentence: High calcium carbonate or citrate supplements can bind the low food phosphorus in the intestine, thus inhibiting its absorption
  • Figure 10.14
  • Table 10.4
  • SLIDE 30: DIETARY INTAKE GUIDELINES This Table contains the Dietary Reference Intakes are the Adequate Intakes (AIs) for Vitamin D (Food and Nutrition Board, Institutes of Medicine, National Academies). Vitamin D is represented in this table as cholecalciferol. The conversion is 1 μg cholecalciferol = 40 IU vitamin D. SCRIPT: 1. In the US, the most current DRIs for Vitamin D were published on January 1, 1997 and remain the current guidelines until further notice. 2. Note that the above DRIs for vitamin D are based on the assumption that the vitamin is not synthesized by exposure to sunlight. 3. Interestingly enough, in the fall of 2008, the Institute of Medicine (IOM) initiated a study to review the Dietary Reference Intakes (DRIs) for vitamin D and calcium, with a report expected for release in the spring of 2010. The review comes as a response to relevant new research on bone health as well as the growing interest in the connection between vitamin D intake and cancer and other chronic disease. 4. Note that the American Academy of Pediatrics has recently updated there guidelines – see next slide
  • New vitamin D recommendations By Rob Stein Despite mounting pressure to urge many Americans to sharply boost their vitamin D levels, new official recommendations are not advocating a huge increase in the amount of the "sunshine vitamin" that people get. The United States and Canada asked the Institute of Medicine, which is part of the National Academy of Sciences, to update the official vitamin D recommendations for the first time since 1997. A 14-member expert committee convened for the task concluded that most Americans and Canadians up to age 70 need no more than 600 international units of vitamin D per day. The elderly may need as much as 800, the committee concluded. Previously, experts called for children and younger adults get 200 international units a day, adults ages 50 to 70 get 400 and the elderly to get 600. But a flurry of research indicating that vitamin D may have a dizzying array of health benefits, and that many people may have insufficient levels , had reignited an intense debate over whether federal guidelines were outdated, leaving millions unnecessarily vulnerable to heart disease, cancer, diabetes, the flu and other ailments. Some doctors have begun routinely testing their patients' vitamin D levels and recommending that people should routinely consume 2,000 or 3,000 international units a day. Sales of vitamin D supplements have increased sharply in recent years. Vitamin D may no longer be called the sunshine vitamin. (Jupiter Images) After reviewing nearly 1,000 published studies along with testimony from scientists and others, the expert committee concluded that vitamin D and calcium play an important role in creating and maintaining strong bones. But the committee concluded that while further research was warranted into vitamin D's role in other health issues, at this point the evidence is mixed and inconclusive. The committee noted that other nutrients, such as vitamin E, were thought to have a host of health benefits, an idea which was later disproved and in some cases found to be dangerous. So the committee recommended that 600 international units a day met the need for almost everyone in the United States and Canada, though people age 71 and older may need as much as 800. The committee also concluded that available evidence does not indicate there are widespread deficiencies, as some have suggested, requiring routine screening. In addition, contrary to what some vitamin D proponents have been urging, the committee did not recommend people increase their sun exposure, citing concerns about skin cancer. Scientists have long known that vitamin D is a vital nutrient that the skin produces when hit by sunlight. The amount varies, depending on where the person lives, skin pigment, age and other factors. With people spending more time indoors and covering up and using sunblock when they do go outside, the amount of vitamin D people create in their bodies has been thought to be falling. But the committee concluded that most people can get sufficient vitamin D from their diets or by taking vitamin D supplements. Milk and other foods are fortified with vitamin D and it occurs naturally in others, such as fatty fish. The recommendations disappointed many proponents of higher vitamin D intakes. Michael Holick of Boston University, one of the leading proponents of the supposed benefits of vitamin D, said he was pleased that the committee recommended higher levels than the previous guidelines. But Holick and others argue that there is more than enough evidence to support taking much more on a routine basis to reduce the risk for a host of health problems. Holick, for example, says he personally takes 3,000 international units a day and advises his patients to do so as well. Holick noted that the committee increased the upper limit of what was considered a safe level of vitamin D to 4,000 for adults. 2010 11 30 00 01 By Rob Stein  | November 30, 2010; 12:01 AM ET New vitamin D recommendations: What they mean A new report from the Institute of Medicine is causing people to reconsider the essential nutrient. Here's what the expert panel said, and why it reached its conclusions. December 06, 2010|By Melissa Healy, Times Staff Writer Every once in a while, some unsung nutrient gets rediscovered and, in the course of a few short years, is rendered virtually magical in the eyes of health professionals and consumers. Foods containing the nutrient come into vogue and supplement use soars. Then, seemingly overnight, the spell is broken. Last week, it was vitamin D's turn to fall from grace. The comedown came courtesy of an expert panel convened by the Institute of Medicine, which advises the government on health issues. The panel's exhaustive report concluded that levels of vitamin D are — thank you very much — just fine in virtually all healthy North Americans. That was surprising to the legions of people who believed that high doses of the vitamin could prevent a laundry list of chronic conditions, including type 2 diabetes, cardiovascular disease, depression, certain cancers, preeclampsia and low birth weight. Their faith in vitamin D, derived from a heap of preliminary studies, prompted many to take mega-doses of the nutrient daily. But the expert panel was unconvinced. It noted that the scientific evidence has been mixed. Moreover, it worried about the risk of undesirable side effects, such as kidney stones, that might come with high levels of supplementation. In short, the jury's still out on the benefits of vitamin D beyond its traditional role in promoting the absorption of calcium for healthy bones. To do that job, virtually all healthy people need only 600 international units (IUs) of vitamin D a day — and those older than 70, 800 IUs. More does not make your bones healthier. So, after all the hype and hope surrounding vitamin D, what's a consumer to do now? Here's a look at what the expert panel said, and why it reached its controversial conclusions. How much vitamin D did the experts say is necessary? For most children, teens and adults, a daily dose of 400 international units (IUs) of the vitamin is sufficient, and 600 IUs recommended. Seniors older than 70 should ideally receive 800 IUs of vitamin D a day, the panel determined. For babies less than 1 year old, the panel considered 400 IUs of vitamin D enough. Those levels are somewhat higher than the ones set in 1997, the last time a government panel examined vitamin D intake. But they are far below what many doctors and supplement advocates had been urging. Why weren't they higher? The idea that people could benefit from daily doses as high as 2,000 IUs is based on the belief that vitamin D can reduce the risk of many chronic diseases, including type 2 diabetes, cardiovascular disease, metabolic disturbances, depression and certain cancers. A slew of recent studies have linked low levels of vitamin D to an increased incidence of these health problems. But the expert panel concluded that the studies were not convincing — many, in fact, showed no such connection — so it based its recommendations only on the amount of vitamin D needed to maintain bone health and prevent fractures. Does that mean I should give up my vitamin D supplements? Maintaining a healthy level of vitamin D through diet alone has become much easier since manufacturers began fortifying foods with the nutrient. Fortified foods — including virtually all milk, many brands of orange juice, and some cheeses, yogurts, margarines and breakfast cereals — are now some of the richest dietary sources of vitamin D. High levels exist naturally in fatty fish such as tuna, salmon and mackerel, and it's also present in egg yolks and beef liver. But there are a lot of people who may still need to add a vitamin D pill to their daily diet. For instance, people who follow a vegan diet need to look hard for supplemental sources of Vitamin D, as do those with milk allergies, lactose intolerance, and people who rarely eat fish. "We didn't actually say in the report that supplementation is verboten," said Dr. Glenville Jones, an endocrinologist at the University of Queensland in Canada who was on the expert panel. So I should keep on buying foods fortified with vitamin D? Definitely, says Katherine Tallmadge, a registered nutritionist and spokeswoman for the American Dietetic Assn., which endorsed the panel's report. In fact, the fortification of foods probably contributed significantly to the panel's finding that most North Americans get enough of the nutrient, even as they raised the recommended daily levels. Can't I get some of the vitamin D I need from the sun? Indeed, the sun is a free, plentiful source of vitamin D. When the sun shines on human skin for at least five to 15 minutes, the body produces the nutrient. But with people spending more time indoors and using sunscreen to prevent skin cancer, this source has fallen on hard times. In fact, the panel didn't even factor in vitamin D from sun exposure when it made its recommendations. Does that mean I should lay off the sunscreen? The sun can be a powerful manufacturer of the nutrient: In 15 minutes, a light-skinned person wearing a bathing suit outside in early July will produce 15,000 to 20,000 IUs of Vitamin D. The body stores excess vitamin D in fat, and some research suggests that it is released as needed. But there's debate about how well that happens, so the panel members suggest that daily dosing of vitamin D is a better bet. Besides, even 15 minutes without sunscreen won't fly with dermatologists. They warn that prolonged exposure to ultraviolet light — either from the sun or in a tanning both — elevates a person's risk of developing melanoma, the deadliest form of skin cancer. So, by all means, slather on that sunscreen. Are there any groups of people for whom the need for vitamin D supplementation is likely to be higher? While the Institute's report assumed away the sun as a source of Vitamin D, they acknowledged that "incidental exposure" plays a role in propping up everybody's levels of the nutrient. For the elderly, that added buffer is largely lost. So among healthy people, those older than 70 need to take in more vitamin D. Breast milk is not a source of vitamin D, so breastfed babies — particularly those who are dark-skinned — should be considered candidates for supplementation from the first week of life. Formula is typically fortified with vitamin D. Patients with kidney disease, including those on dialysis, are at particular risk of vitamin D deficiency — although they'll need to be very careful if they already have an elevated risk for kidney stones, as levels that are too high can exacerbate that risk. Some prescription medications, including the anti-seizure drugs Phenobarbital, Dilantin and Tegretol, appear to depress levels of circulating vitamin D, suggesting that some people with epilepsy should consider supplementation. Diuretics called thiazides, which are used to treat high blood pressure and kidney stones, can increase levels of Vitamin D in the bloodstream. I was told I was deficient in vitamin D. Is it true? Vitamin D deficiency has been defined and tested in widely varying ways. Labs tests for the nutrient have used different standards, different methods and sometimes test for different indicators of vitamin D deficiency. So the first things to ask are: Who told you were deficient, and what measure did they use? Physicians and dieticians reading the IOM report's specialized appendices may be reconsidering what constitute sufficiency in the coming months. Is there such a thing as too much vitamin D? The expert panel's comprehensive report is unlikely to lay this question to rest, although its advice was clear: Taking more than 4,000 IUs of vitamin D a day is risky. Too much Vitamin D can cause kidney stones and hypercalcemia, which in turn can lead to headaches, anxiety, depression, fatigue, stomach pain, cardiac arrhythmia, muscle weakness, aches, pains and fractures. Daily doses above 10,000 IUs a day are known to cause tissue and kidney damage, the panel said. In thinking about the safe upper limit that the panel proposed, keep in mind that the experts were looking for the amount needed by healthy people to maintain their bones. Since the panel wasn't convinced that higher levels of vitamin D could prevent or treat other diseases, it had little tolerance for the risks associated with mega-doses. What are the prospects for clearing up this confusion? In coming years, research will begin to clarify both sides of that equation and draw a clearer picture of the risks that kick in at higher levels of supplementation, as well as the conditions that such supplementation can treat or prevent. Harvard University researchers are enrolling 20,000 subjects for a study to compare rates of cancer, heart disease, diabetes, cognitive decline, depression and respiratory diseases in people randomly chosen to receive a daily dose of 2,000 IUs of vitamin D versus other subjects who get a placebo. Ongoing trials in Israel and India will assess how a year's worth of monthly supplementation with 10,000 IUs of vitamin D affects the development of insulin resistance, metabolic syndrome and diabetes in obese women, and with what side effects. A University of Colorado study will compare rates of respiratory infections among elderly nursing home patients taking as much as 4,000 IUs of vitamin D a day compared to those taking a smaller dose of 400 to 1,000 IUs daily.
  • Figure 10.7
  • Ch10 Bone Health

    1. 1. Chapter 10 Nutrients Involved in Bone Health Lecture and Animation PowerPoint Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. To run the animations you must be in Slideshow View . Use the buttons on the animation to play, pause, and turn audio/text on or off. Please Note : Once you have used any of the animation controls , you must click in the white background before advancing to the next slide.
    2. 2. Nutrients Involved in Bone Health: Lecture Outline <ul><li>Bones: </li></ul><ul><ul><li>Structure </li></ul></ul><ul><ul><li>Growth & remodeling </li></ul></ul><ul><ul><li>Bone health </li></ul></ul><ul><ul><li>Osteoporosis </li></ul></ul><ul><ul><li>Bone health assessment </li></ul></ul><ul><li>Nutrients for Bone Growth, Maintenance & Repair: </li></ul><ul><ul><li>Calcium </li></ul></ul><ul><ul><li>Phosphorus </li></ul></ul><ul><ul><li>Vitamin D </li></ul></ul><ul><ul><li>Magnesium </li></ul></ul><ul><ul><li>Fluoride </li></ul></ul>
    3. 3. Bone Structure <ul><li>Periosteum </li></ul><ul><li>Cortical & trabecular bone </li></ul><ul><li>Bone marrow </li></ul>
    4. 4. Bone Structure
    5. 5. Bone Growth & Remodeling <ul><li>Bone remodeling : degradation & resynthesis of bone </li></ul><ul><li>Resorption : losing substance; bone resorption is part of initial process for remodeling & growth </li></ul>
    6. 6. Bone Growth & Remodeling <ul><li>Bone is composed of approximately: </li></ul><ul><ul><li>65% minerals </li></ul></ul><ul><ul><li>35% connective tissue </li></ul></ul><ul><li>Peak bone mass is achieved by age 30 </li></ul><ul><li>After 30 – bone resorption occurs at rate faster than bone synthesis </li></ul><ul><li>This leads to ↓ in bone mass & bone mineral density </li></ul>
    7. 7.
    8. 8. Influencing Bone Health: Biological Factors
    9. 9. Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at
    10. 10. Influencing Bone Health: Modifiable Lifestyle Factors
    11. 11. Increasing Bone Density
    12. 12. Osteoporosis <ul><li>Low bone mineral density that leads to porous and fragile bones </li></ul>
    13. 13. Osteoporosis
    14. 14. Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at
    15. 15. Osteoporosis Facts <ul><li>Osteoporosis in the US (2010) </li></ul><ul><ul><li>9.1 million women </li></ul></ul><ul><ul><li>2.8 million men </li></ul></ul><ul><li>Osteoporosis in the US -> </li></ul><ul><ul><li>1.5 million bone fractures per year </li></ul></ul><ul><ul><li>300,000 broken hips </li></ul></ul>
    16. 16. Significance of Hip Fracture <ul><li>Hip fractures -> </li></ul><ul><ul><li>Loss of mobility </li></ul></ul><ul><ul><li>Loss of independence </li></ul></ul><ul><ul><li>↑ need for long term care </li></ul></ul><ul><ul><li>Significant association with ↑ mortality </li></ul></ul>
    17. 17. Impact of Poor Bone Health
    18. 18. Osteoporosis Classification <ul><li>Type 1 Osteoporosis: </li></ul><ul><ul><li>Aka postmenopausal osteoporosis </li></ul></ul><ul><ul><li>Women 50-60 y.o. </li></ul></ul><ul><ul><li>Linked to ↓ estrogen </li></ul></ul><ul><ul><li>Affects trabecular bone undergoing rapid remodeling </li></ul></ul><ul><li>Type 2 Osteoporosis: </li></ul><ul><ul><li>Both men & women </li></ul></ul><ul><ul><li>Later in life: 70-75 y.o. </li></ul></ul><ul><ul><li>Breakdown of cortical & trabecular bone </li></ul></ul><ul><ul><li>From combination of dietary & age-related factors (bone loss & ↓ ability of kidney to make calcitriol – most active form of vitamin D) </li></ul></ul>
    19. 19.
    20. 20.
    21. 21.
    22. 22. Bone Health Assessment: DXA <ul><li>Dual energy x-ray absorptiometry </li></ul><ul><li>20-30 minute whole body scan </li></ul><ul><li>Bone blocks path of low level x-ray </li></ul><ul><li>DXA measurement generates T score: </li></ul><ul><ul><li>Normal bone density is 0 to -1 T score </li></ul></ul><ul><ul><li>Low bone mineral density is -1 to -2.4 </li></ul></ul><ul><ul><li>Osteoporosis is -2.5 or lower </li></ul></ul>
    23. 23. Who Should Have DXA? <ul><li>All women age 65+ and men 70+ </li></ul><ul><li>Younger postmenopausal women aged 50-69 who are at risk </li></ul><ul><li>Perimenopausal women with low body weight, prior low-trauma fracture, on high risk mediations (ex: steroids) </li></ul><ul><li>Adults with fracture after age 50 </li></ul><ul><li>Adults with health conditions on long-term steroids </li></ul><ul><li>Anyone being considered for osteoporosis meds </li></ul>
    24. 24. Critical Nutrients Required for Bone Growth, Maintenance & Repair <ul><li>Calcium </li></ul><ul><li>Phosphorus </li></ul><ul><li>Vitamin D </li></ul><ul><li>Magnesium </li></ul><ul><li>Fluoride </li></ul>
    25. 25. Calcium: Functions <ul><li>Represents 40% of all minerals in body </li></ul><ul><li>Bone growth, development & maintenance </li></ul><ul><li>Blood clot formation </li></ul><ul><li>Muscle contraction </li></ul><ul><li>Cellular metabolism </li></ul><ul><li>Maintaining cell integrity </li></ul><ul><li>Promoting cell differentiation </li></ul>
    26. 26. Calcium: Health Benefits Beyond Bones <ul><li>↑ calcium intake & ↓ risk bone fractures </li></ul><ul><li>Adequate Ca & ↓ risk of colon cancer </li></ul><ul><li>↓ risk of kidney stone formation </li></ul><ul><li>↓ lead absorption </li></ul><ul><li>800-1,200 mg Ca/day & ↓ BP </li></ul><ul><li>1,200 mg Ca/day + low fat, low cholesterol diet can improve lipid profile if ↑ chol </li></ul>
    27. 27. Calcium: Deficiency <ul><li>↓ bone mineral density </li></ul><ul><li>Osteopenia </li></ul><ul><li>Osteoporosis </li></ul><ul><li>↑ risk of fracture </li></ul>
    28. 28. Calcium: Excess <ul><li>UL is 2,500 mg </li></ul><ul><li>Ca supplements can cause: </li></ul><ul><ul><li>Gas </li></ul></ul><ul><ul><li>Bloating </li></ul></ul><ul><ul><li>Constipation </li></ul></ul><ul><li>↑↑ intake of calcium can: </li></ul><ul><ul><li>↑ risk of kidney stones </li></ul></ul><ul><ul><li>↑ urinary & blood calcium levels -> headaches, kidney failure, tissue calcification & ↓ absorption of other minerals </li></ul></ul>
    29. 29. Calcium: Nutrient Needs <ul><li>No RDA </li></ul><ul><li>AI is 1,000 mg/day for adults up to 50 </li></ul><ul><li>AI is 1,200 mg/day for adults 51+ y.o. </li></ul><ul><li>Average US intake: </li></ul><ul><ul><li>800 mg/day for women </li></ul></ul><ul><ul><li>1,000 mg/day for men </li></ul></ul>
    30. 30.
    31. 31. Calcium Absorption <ul><li>Calcium absorption increased by: </li></ul><ul><ul><li>High need – growth, pregnancy, lactation </li></ul></ul><ul><ul><li>↑ levels of parathyroid hormone & vit D </li></ul></ul><ul><ul><li>Lactose present in diet </li></ul></ul><ul><ul><li>Food contents moving through GI tract </li></ul></ul><ul><ul><li>Acidic environment of stomach </li></ul></ul><ul><li>Calcium absorption decreased by: </li></ul><ul><ul><li>Phytic acid </li></ul></ul><ul><ul><li>Oxalates </li></ul></ul><ul><ul><li>Tannins </li></ul></ul><ul><ul><li>Vitamin D deficiency </li></ul></ul><ul><ul><li>Diarrhea </li></ul></ul><ul><ul><li>Increasing age </li></ul></ul><ul><ul><li>Certain medications </li></ul></ul>
    32. 32. Calcium: Dietary Sources <ul><li>Best sources are dairy: </li></ul><ul><ul><li>Milk </li></ul></ul><ul><ul><li>Yogurt </li></ul></ul><ul><ul><li>Cheese </li></ul></ul><ul><li>Non-dairy sources include: </li></ul><ul><ul><li>Dark green leafy vegetables </li></ul></ul><ul><ul><li>Almonds, legumes </li></ul></ul><ul><ul><li>Sardines </li></ul></ul><ul><ul><li>Canned salmon </li></ul></ul><ul><ul><li>Calcium-fortified juice </li></ul></ul>
    33. 33.
    34. 34. Calcium Supplements <ul><li>Recommended for: </li></ul><ul><ul><li>Lactose intolerant </li></ul></ul><ul><ul><li>Milk allergies </li></ul></ul><ul><ul><li>Ovo-vegetarian </li></ul></ul><ul><ul><li>Vegan </li></ul></ul><ul><ul><li>Low calcium diets </li></ul></ul><ul><li>Supplements: </li></ul><ul><ul><li>Keep to 500 mg/less per dose </li></ul></ul><ul><ul><li>Look for USP label </li></ul></ul><ul><ul><li>Calcium carbonate: </li></ul></ul><ul><ul><ul><li>40% calcium </li></ul></ul></ul><ul><ul><ul><li>Take with food </li></ul></ul></ul><ul><ul><li>Calcium citrate: </li></ul></ul><ul><ul><ul><li>21% calcium </li></ul></ul></ul><ul><ul><ul><li>Doesn ’t require food </li></ul></ul></ul>
    35. 35. Phosphorus: Functions <ul><li>Component of hydroxyapatite – contributes to bone and teeth strength </li></ul><ul><li>Part of DNA & RNA & critical for cellular replication </li></ul><ul><li>Primary component of ATP </li></ul><ul><li>Allows enzymes & B vitamins to function </li></ul><ul><li>Component of phospholipid membrane </li></ul><ul><li>Maintains blood pH and fluid balance </li></ul>
    36. 36. Phosphorus: Deficiency <ul><li>Found in: </li></ul><ul><ul><li>Preterm infants </li></ul></ul><ul><ul><li>Vegans </li></ul></ul><ul><ul><li>Alcoholics </li></ul></ul><ul><ul><li>Nutrient poor diets </li></ul></ul><ul><ul><li>Persistent diarrhea </li></ul></ul>
    37. 37. Phosphorus: Excess <ul><li>UL is 3-4 g/day </li></ul><ul><li>↑↑ intake ↑ risk of tissue calcification & stone formation </li></ul><ul><li>Chronic imbalance in phosphorus:calcium ratio can ↑ risk of ↓ bone mineral density </li></ul>
    38. 38. Phosphorus: Nutrient Needs <ul><li>Absorption enhanced by presence of vit D </li></ul><ul><li>RDA is [INSERT RDA/DRI] </li></ul><ul><li>Most N. Americans meet/exceed RDA </li></ul>
    39. 39. Phosphorus: Dietary Sources <ul><li>Naturally abundant in many foods </li></ul><ul><li>Milk, cheese, meat, bread </li></ul><ul><li>Nuts, fish, breakfast cereals, bran, eggs </li></ul><ul><li>From food additives </li></ul>
    40. 40.
    41. 41. Vitamin D <ul><li>Produced in the skin when exposed to UV light </li></ul><ul><li>Cholesterol is vitamin D precursor </li></ul><ul><li>Vitamin D is a hormone </li></ul><ul><li>Activation occurs in liver & kidneys </li></ul>
    42. 42.
    43. 43. Vitamin D: Functions <ul><li>Maintains calcium & phosphorus in blood </li></ul><ul><li>Binds to and affects cells of: </li></ul><ul><ul><li>Immune system </li></ul></ul><ul><ul><li>Brain & nervous system </li></ul></ul><ul><ul><li>Skin </li></ul></ul><ul><ul><li>Muscles </li></ul></ul><ul><ul><li>Reproductive organs </li></ul></ul><ul><li>May ↓ certain types of cancer risk </li></ul>
    44. 44. Vitamin D & Sunlight <ul><li>Amount of sun exposure needed to activate vitamin D is affected by: </li></ul><ul><li>Skin color </li></ul><ul><li>Age </li></ul><ul><li>Time of day </li></ul><ul><li>Latitude & strength of UV light </li></ul><ul><li>Exposure time </li></ul><ul><li>Season </li></ul>
    45. 45.
    46. 46. Vitamin D: Deficiency <ul><li>↑ deficiency risk in: </li></ul><ul><ul><li>Dark skinned people </li></ul></ul><ul><ul><li>Low vitamin D diet </li></ul></ul><ul><ul><li>Exclusively breastfed infants </li></ul></ul><ul><ul><li>Elderly </li></ul></ul><ul><ul><li>Insufficient sun exposure </li></ul></ul><ul><ul><li>Diet without fortified foods </li></ul></ul><ul><li>With ↓ levels of vit D: </li></ul><ul><ul><li>Intestinal Ca absorption ↓ </li></ul></ul><ul><ul><li>Rickets </li></ul></ul><ul><ul><li>Osteomalacia </li></ul></ul>
    47. 47.
    48. 48. Vitamin D: Excess <ul><li>UL is 100 mcg (4000 IU) per day NOTE: THIS WAS UPDATED IN NOV 2010, use this guideline, NOT the one in your book (it is outdated) </li></ul><ul><li>↑↑ vitamin D intake -> ↑ blood calcium </li></ul><ul><li>Toxicity symptoms: </li></ul><ul><ul><li>Weakness </li></ul></ul><ul><ul><li>Loss of appetite </li></ul></ul><ul><ul><li>Diarrhea & vomiting </li></ul></ul><ul><ul><li>Confusion </li></ul></ul><ul><ul><li>↑ urine output </li></ul></ul><ul><li>Toxicity does not occur from sun source </li></ul>
    49. 49. Pre-2010 Dietary Intake Guidelines Life Stage (Ages) Infants & Children Men & Women Pregnancy & Lactation Birth – 13 5 mcg (200 IU) 14 – 18 5 mcg (200 IU) 5 mcg (200 IU) 19 – 50 5 mcg (200 IU) 5 mcg (200 IU) 51 – 70 10 mcg (400 IU) 71 + 15 mcg (600 IU)
    50. 50. 2010 UPDATED Dietary Intake Guidelines NEW RECS: 400 IU (Infants) 600 IU (Adults) 800 IU (70+ years) Life Stage (Ages) Infants & Children Men & Women Pregnancy & Lactation Birth – 12 months 10 mcg (400 IU) 1– 18 yr 15 mcg (600 IU) 15 mcg (600 IU) 19 – 50 yr 15 mcg (600 IU) 15 mcg (600 IU) 51 – 70 yr 15 mcg (600 IU) 71 + yr 20 mcg (800 IU)
    51. 51. Vitamin D: Nutrient Needs <ul><li>Use updated guidelines on these slides (see previous slide, number 50) </li></ul><ul><li>Your book has the outdated guidelines! </li></ul>
    52. 52. Vitamin D: Fortification & Supplementation <ul><li>1 cup milk = 100 IU vitamin D </li></ul><ul><li>2008, American Academy of Pediatrics recommends 400 IU/day for: </li></ul><ul><ul><li>Children & adolescents with <400 IU/day intake </li></ul></ul><ul><ul><li>Exclusively breastfed infants beginning within the first few days of life </li></ul></ul>
    53. 53. Vitamin D: Dietary Sources <ul><li>Dietary sources are limited </li></ul><ul><li>Fatty fish (ex: salmon & sardines) </li></ul><ul><li>Fortified dairy foods </li></ul><ul><li>Fortified breakfast cereals </li></ul>
    54. 54.
    55. 55. Magnesium: Functions <ul><li>Nerve & heart function </li></ul><ul><li>Assists enzymatic reactions </li></ul><ul><li>Provides rigidity to bones </li></ul>
    56. 56. Magnesium: Deficiency <ul><li>Deficiency causes: </li></ul><ul><ul><li>↓ bone strength & bone volume </li></ul></ul><ul><ul><li>Poor bone development </li></ul></ul><ul><ul><li>↓ bone formation </li></ul></ul><ul><ul><li>↑ bone resorption </li></ul></ul><ul><ul><li>Helps relax muscles after contraction </li></ul></ul><ul><ul><li>Stabilizes calcium in enamel -> strong teeth </li></ul></ul><ul><ul><li>300+ enzymes require Mg for their activity </li></ul></ul>
    57. 57. Magnesium: Deficiency <ul><li>Deficiency symptoms: </li></ul><ul><ul><li>Irregular heartbeat </li></ul></ul><ul><ul><li>Weakness </li></ul></ul><ul><ul><li>Muscle pain </li></ul></ul><ul><ul><li>Disorientation </li></ul></ul><ul><ul><li>Seizures </li></ul></ul>
    58. 58. Magnesium Absorption <ul><li>↑ phosphorus diet ↓ Mg absorption </li></ul><ul><li>↑ fiber (phytate) diet ↓ Mg absorption </li></ul><ul><li>↓ protein diet ↓ Mg absorption </li></ul><ul><li>Magnesium loss can be caused by: </li></ul><ul><ul><li>Heavy perspiration </li></ul></ul><ul><ul><li>Prolonged vomiting or diarrhea </li></ul></ul><ul><ul><li>Diuretic use </li></ul></ul><ul><ul><li>Alcohol abuse (↑ urinary Mg excretion) </li></ul></ul>
    59. 59. Magnesium: Excess <ul><li>UL: 350 mg/day </li></ul><ul><li>Excessive Mg intake -> diarrhea </li></ul><ul><li>Non-food sources can cause problems; dietary sources rarely problematic </li></ul><ul><li>Toxicity can occur in: </li></ul><ul><ul><li>People with kidney failure </li></ul></ul><ul><ul><li>Abuse of OTC laxatives & antacids with Mg (ex: milk of magnesia) </li></ul></ul><ul><ul><li>Elderly people at ↑ risk toxicity </li></ul></ul>
    60. 60. Magnesium: Nutrient Needs <ul><li>RDA: </li></ul><ul><ul><li>400 mg/day for men </li></ul></ul><ul><ul><li>310 mg/day for women </li></ul></ul><ul><li>DV on food labels: 400 mg/day </li></ul><ul><li>Average US consumption is < RDA meaning we should ↑ consumption of Mg-rich foods </li></ul><ul><li>Refining grains ↓ Mg content by 80% </li></ul>
    61. 61. Magnesium: Dietary Sources <ul><li>Found in chlorophyll & comes from plant sources: </li></ul><ul><ul><li>Squash, whole grains, bran, beans, nuts, seeds, broccoli </li></ul></ul><ul><li>Animal products: </li></ul><ul><ul><li>Milk & meats </li></ul></ul><ul><li>Some magnesium in chocolate </li></ul><ul><li>Hard tap water </li></ul><ul><li>Coffee (espresso, not brewed) </li></ul>
    62. 62.
    63. 63. Fluoride: Functions <ul><li>Prevents dental caries by: </li></ul><ul><ul><li>Contributing to strength of teeth structure & resists bacterial acid degradation </li></ul></ul><ul><ul><li>Stimulates remineralization of enamel </li></ul></ul><ul><ul><li>Producing antibacterial effect of acid producing organisms found in enamel </li></ul></ul>
    64. 64. Fluoride: Deficiency <ul><li>↑ risk of dental caries </li></ul>
    65. 65. Fluoride: Excess <ul><li>UL is 1.3-2.2 mg/day for kids </li></ul><ul><li>UL is 10 mg for people aged 9+ </li></ul><ul><li>Fluorosis can occur from excessive intake of fluoridated toothpaste (↑ risk for kids) </li></ul><ul><li>Fluorosis permanently damages teeth -> stained & pitted teeth </li></ul><ul><li>Recommend to kids: </li></ul><ul><ul><li>Don ’t swallow toothpaste </li></ul></ul><ul><ul><li>Use pea-sized portion </li></ul></ul>
    66. 66. Fluorosis: Mottled Teeth
    67. 67. Fluoride: Nutrient Needs <ul><li>AI: 3.1-3.8 mg/day </li></ul><ul><li>1 cup of fluoridated water = 0.25 mg/cup </li></ul><ul><li>This level helps: </li></ul><ul><ul><li>Prevent dental caries </li></ul></ul><ul><ul><li>Without ↑ risk of ill effects </li></ul></ul>
    68. 68. Fluoride: Dietary Sources <ul><li>Marine fish, clams, lobster, shrimp </li></ul><ul><li>Tea </li></ul><ul><li>Seaweed </li></ul><ul><li>Some natural water sources </li></ul><ul><li>Fluoridated water sources (not usually bottled water) </li></ul>
    69. 69.
    70. 70. Boron <ul><li>Plays role in structure & function of bone by: </li></ul><ul><ul><li>Influencing transport of calcium across membranes and </li></ul></ul><ul><ul><li>Synthesizing vitamin D </li></ul></ul><ul><li>↓ boron levels -> ↓ blood levels of Ca & Mg </li></ul><ul><li>Daily requirement: 1 mg/day </li></ul><ul><li>UL: 20 mg/day </li></ul>
    71. 71. Silicon <ul><li>Aids in normal bone & connective tissue growth & development </li></ul><ul><li>Helps synthesize collagen </li></ul><ul><li>No UL established </li></ul><ul><li>Toxicity in people on ↑↑ dose supplements for many years </li></ul><ul><li>Toxicity -> ↑ kidney stone risk & ↓ antioxidant levels </li></ul>