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Kamis, 29 Mei 2008
Rabu, 28 Mei 2008
Rosemary Can Protect the Brain From Dementia and Alzheimer's Disease
Rosemary is an herb with a distinctly woody taste and fragrant evergreen needle-like leaves that can deliciously transform our food. In addition to its food enhancing properties, rosemary is a potent brain protector. Ancient Greeks believed it profoundly improved memory. Greek students used to wear a wreath while sitting examinations for potent brain power.
Recent studies have now confirmed what the Greeks knew long ago. Rosemary contains an ingredient that fights off free radical damage in the brain. This active ingredient, known as carnosic acid (CA), can protect the brain from stroke and neurodegeneration that is due to toxins and free radicals which are thought to be one of the contributors to stroke and conditions such as Alzheimer’s and dementia.
Research published in both The Journal of Neurochemistry and Nature Reviews Neuroscience, has revealed that CA activates a signaling pathway that protects brain cells from the free radical damage.
Rosemary is believed to prevent normal brain aging and keep the brain youthful and sharp. This tasty herb is also thought to improve memory.
Recent studies have now confirmed what the Greeks knew long ago. Rosemary contains an ingredient that fights off free radical damage in the brain. This active ingredient, known as carnosic acid (CA), can protect the brain from stroke and neurodegeneration that is due to toxins and free radicals which are thought to be one of the contributors to stroke and conditions such as Alzheimer’s and dementia.
Research published in both The Journal of Neurochemistry and Nature Reviews Neuroscience, has revealed that CA activates a signaling pathway that protects brain cells from the free radical damage.
Rosemary is believed to prevent normal brain aging and keep the brain youthful and sharp. This tasty herb is also thought to improve memory.
Senin, 26 Mei 2008
Black Cohosh Herb Halts Growth of Breast Cancer Tumors
Extract of black cohosh may halt the growth of breast cancer cells, according to a new study conducted by the French company Naturex and published in the journal "Phytomedicine." The study was funded by the National Institutes of Health and the Susan G. Komen Breast Cancer Foundation.
Cimicifugae racemosae rhizome, also known as black cohosh, is a plant in the buttercup family that is native to eastern North America, ranging from central Georgia in the south to southern Ontario in the north, and as far west as Missouri. It is also known as black bugbane, black snakeroot and fairy candle.
Black cohosh has a history of use as a traditional medicine for gynecological problems, kidney problems and sore throat, and is commonly used to help relieve the symptoms of menopause.
In the current study, researchers applied extracts of black cohosh to breast cancer cells in a laboratory setting. Growth of cancer cells was inhibited in cell lines that had the extract added, apparently due to an increase in programmed cell death (apoptosis).
The researchers linked the cancer-inhibiting effects of black cohosh extract to its content of triterpene glycosides.
Vitamin survey : startling health benefits and reductions in the risk of disease
While fruit and vegetables are a prime source of the vitamins we need, it takes 66 oranges to supply our recommended daily requirement of vitamin C, a nutritionist says
Despite well-entrenched beliefs to the contrary, supplements really do have beneficial effects, writes Andrea Nagel
The more supplements you take the healthier you are, says a new study published in the Nutrition Journal conducted by Gladys Block at the University of California.
People who rely on supplements to augment their diets have long been thought to be “just making expensive urine”. But the study argues that taking supplements can drastically improve one’s health.
Patrick Holford, who was in South Africa last week to promote his latest book, Optimum Nutrition Made Easy, co-written with Susannah Lawson, agrees.
He believes that the findings of the survey are completely consistent with the emerging science helping to define what “optimum nutrition” really means.
He says: “On the basis of studying the science of nutrition for the last 30 years, I take five different supplements twice a day , as well as following as healthy a diet as possible.”
Holford consumes the following cocktail of supplements:
1. A high-strength multivitamin (that should provide 15mcg of vitamin D and other high minerals);
2. vitamin C, together with zinc and berry extracts, essential omega 3 and 6 fats;
3. phospholipids (phosphatidyl choline, serine, DMAE) and other brain-friendly nutrients including the amino acid pyroglutamate; and
4. extra antioxidants including glutathione, alpha-lipoic acid, co-enzyme Q10, selenium and resveratrol.
“I also occasionally take digestive enzymes, probiotics and glutamine powder if I have any digestive problems, extra chromium if my energy is low, niacin (B3) if I get a headache, extra vitamin A if I have an infection, and extra magnesium if I’m stressed” he says. “If I have an allergic reaction I take extra quercitin with MSM, glutamine, vitamin C and bromelain.”
The Nutrition Journal survey of October 2007 involved testing three groups of people: one that took no supplements, one that took a single multivitamin and one that took a combination of various vitamins according to the needs of their bodies.
Commenting on the survey, Holford says: “The multi-supplement takers who customised their selection were the most optimally healthy and had the optimum levels of nutrients in their blood even though the body excretes more than half of what it uses.”
The study was partly motivated by the concern that taking large amount of supplemental nutrients might lead to adverse effects from overdosing, but the results showed startling health benefits and disease risk reductions the more supplements were taken, with no apparent downside, except perhaps the cost.
Holford does insist that the correct diet is essential for maintaining not only good health but also abundant energy, ideal weight, great skin, no pain, a happy and motivated mood and a sharp mind and memory.
He also insists that an optimal diet can strengthen the immune system, balance hormones and produce a trouble-free digestive system.
“Our species has lost the sense of what we’re supposed to eat” he says.
“I eat like a gorilla and supplement because I can’t get enough nutrients and minerals from my diet.”
Holford says to maintain the recommended daily dose of vitamin C, we have to eat 66 supermarket oranges, a good reason to take a supplement.
A high level of vitamin C in the body helps protect your health, he says, but he is quick to admit that each body has its own distinct needs that depend on a whole host of factors — including the effects of our environment.
“That’s why saying that we all need 60mg of vitamin C each day (which is the UK government’s recommended intake for adults) is like saying we all need size 10 shoes.”
Holford’s proposed mission is to help the individual work out his or her specific needs to provide optimum nutrition.
“I want to help people to feel 100percent healthy, to help them keep fit and happy and prevent them from getting sick.”
He believes that most sicknesses are preventable if you have the right lifestyle and consume optimum nutrition.
Despite well-entrenched beliefs to the contrary, supplements really do have beneficial effects, writes Andrea Nagel
The more supplements you take the healthier you are, says a new study published in the Nutrition Journal conducted by Gladys Block at the University of California.
People who rely on supplements to augment their diets have long been thought to be “just making expensive urine”. But the study argues that taking supplements can drastically improve one’s health.
Patrick Holford, who was in South Africa last week to promote his latest book, Optimum Nutrition Made Easy, co-written with Susannah Lawson, agrees.
He believes that the findings of the survey are completely consistent with the emerging science helping to define what “optimum nutrition” really means.
He says: “On the basis of studying the science of nutrition for the last 30 years, I take five different supplements twice a day , as well as following as healthy a diet as possible.”
Holford consumes the following cocktail of supplements:
1. A high-strength multivitamin (that should provide 15mcg of vitamin D and other high minerals);
2. vitamin C, together with zinc and berry extracts, essential omega 3 and 6 fats;
3. phospholipids (phosphatidyl choline, serine, DMAE) and other brain-friendly nutrients including the amino acid pyroglutamate; and
4. extra antioxidants including glutathione, alpha-lipoic acid, co-enzyme Q10, selenium and resveratrol.
“I also occasionally take digestive enzymes, probiotics and glutamine powder if I have any digestive problems, extra chromium if my energy is low, niacin (B3) if I get a headache, extra vitamin A if I have an infection, and extra magnesium if I’m stressed” he says. “If I have an allergic reaction I take extra quercitin with MSM, glutamine, vitamin C and bromelain.”
The Nutrition Journal survey of October 2007 involved testing three groups of people: one that took no supplements, one that took a single multivitamin and one that took a combination of various vitamins according to the needs of their bodies.
Commenting on the survey, Holford says: “The multi-supplement takers who customised their selection were the most optimally healthy and had the optimum levels of nutrients in their blood even though the body excretes more than half of what it uses.”
The study was partly motivated by the concern that taking large amount of supplemental nutrients might lead to adverse effects from overdosing, but the results showed startling health benefits and disease risk reductions the more supplements were taken, with no apparent downside, except perhaps the cost.
Holford does insist that the correct diet is essential for maintaining not only good health but also abundant energy, ideal weight, great skin, no pain, a happy and motivated mood and a sharp mind and memory.
He also insists that an optimal diet can strengthen the immune system, balance hormones and produce a trouble-free digestive system.
“Our species has lost the sense of what we’re supposed to eat” he says.
“I eat like a gorilla and supplement because I can’t get enough nutrients and minerals from my diet.”
Holford says to maintain the recommended daily dose of vitamin C, we have to eat 66 supermarket oranges, a good reason to take a supplement.
A high level of vitamin C in the body helps protect your health, he says, but he is quick to admit that each body has its own distinct needs that depend on a whole host of factors — including the effects of our environment.
“That’s why saying that we all need 60mg of vitamin C each day (which is the UK government’s recommended intake for adults) is like saying we all need size 10 shoes.”
Holford’s proposed mission is to help the individual work out his or her specific needs to provide optimum nutrition.
“I want to help people to feel 100percent healthy, to help them keep fit and happy and prevent them from getting sick.”
He believes that most sicknesses are preventable if you have the right lifestyle and consume optimum nutrition.
Minggu, 25 Mei 2008
Omega 3 vs omega 6 fatty acids
Omega 3 and omega 6 are types of essential fatty acids - meaning we can't make them on our own and have to obtain them from our diet. They're poly- unsaturated fatty acids that differ from each other in their chemical structure.
In modern diets, there are few sources of omega 3 fatty acids, mainly the fat of cold-water fish, such as salmon, sardines, herring, mackerel, black cod and bluefish.
There are two critical omega 3 fatty acids that the body needs, eicosapentaenoic acid (called EPA) and docosahexaenoic acid (or DHA). Vegetarian sources, such as walnuts and flaxseed, contain a precursor omega 3 (alpha-linolenic acid, called ALA) that the body must convert to EPA and DHA. EPA and DHA are the building blocks for hormones that control immune function, blood clotting and cell growth as well as components of cell membranes.
By contrast, sources of omega 6 fatty acids are numerous in modern diets. They're found in seeds and nuts and the oils extracted from them. Refined vegetable oils, such as soy oil, are used in most of the snack foods, cookies, crackers and sweets in the American diet, as well as in fast food. Soybean oil alone is so ubiquitous in fast foods and processed foods that an astounding 20 percent of the calories in the American diet are estimated to come from it.
The body also constructs hormones from omega 6 fatty acids. In general, hormones derived from the two classes of essential fatty acids have opposite effects. Those from omega 6 fatty acids tend to increase inflammation (an important component of the immune response), blood clotting and cell proliferation, while those from omega 3 fatty acids decrease those functions. The two families of hormones must be in balance to maintain optimum health.
Many nutrition experts believe that before we relied so heavily on processed foods, humans consumed omega 3 and omega 6 fatty acids in roughly equal amounts. But to our great detriment, most North Americans and Europeans now get far too much of the omega 6s and not enough of the omega 3s. This dietary imbalance may explain the rise of such diseases as asthma, coronary heart disease, many forms of cancer, autoimmunity and neurodegenerative diseases, all of which are believed to stem from inflammation in the body.
The imbalance between omega 3 and omega 6 fatty acids may also contribute to obesity, depression, dyslexia, hyperactivity and even a tendency toward violence.
Bringing the fats into proper proportion may relieve those conditions, says Joseph Hibbeln, M.D., a psychiatrist at the National Institutes of Health and perhaps the world's leading authority on the relationship between fat consumption and mental health. At the 2006 Nutrition and Health Conference sponsored by the University of Arizona's College of Medicine and Columbia University's College of Physicians and Surgeons, Hibbeln cited a study showing that violence in a British prison dropped by 37 percent after omega 3 oils and vitamins were added to the prisoners' diets.
If you follow my anti-inflammatory diet (available on my Web site), you should get a healthy ratio of these fatty acids. In general, however, you can cut down on omega 6 levels by reducing consumption of processed and fast foods and polyunsaturated vegetable oils (corn, sunflower, safflower and soy, for example). At home, use extra-virgin olive oil for cooking and in salad dressings. Eat more oily fish (or take fish-oil supplements), walnuts, freshly ground flaxseed and omega 3-fortified eggs. Your body and mind will thank you.
In modern diets, there are few sources of omega 3 fatty acids, mainly the fat of cold-water fish, such as salmon, sardines, herring, mackerel, black cod and bluefish.
There are two critical omega 3 fatty acids that the body needs, eicosapentaenoic acid (called EPA) and docosahexaenoic acid (or DHA). Vegetarian sources, such as walnuts and flaxseed, contain a precursor omega 3 (alpha-linolenic acid, called ALA) that the body must convert to EPA and DHA. EPA and DHA are the building blocks for hormones that control immune function, blood clotting and cell growth as well as components of cell membranes.
By contrast, sources of omega 6 fatty acids are numerous in modern diets. They're found in seeds and nuts and the oils extracted from them. Refined vegetable oils, such as soy oil, are used in most of the snack foods, cookies, crackers and sweets in the American diet, as well as in fast food. Soybean oil alone is so ubiquitous in fast foods and processed foods that an astounding 20 percent of the calories in the American diet are estimated to come from it.
The body also constructs hormones from omega 6 fatty acids. In general, hormones derived from the two classes of essential fatty acids have opposite effects. Those from omega 6 fatty acids tend to increase inflammation (an important component of the immune response), blood clotting and cell proliferation, while those from omega 3 fatty acids decrease those functions. The two families of hormones must be in balance to maintain optimum health.
Many nutrition experts believe that before we relied so heavily on processed foods, humans consumed omega 3 and omega 6 fatty acids in roughly equal amounts. But to our great detriment, most North Americans and Europeans now get far too much of the omega 6s and not enough of the omega 3s. This dietary imbalance may explain the rise of such diseases as asthma, coronary heart disease, many forms of cancer, autoimmunity and neurodegenerative diseases, all of which are believed to stem from inflammation in the body.
The imbalance between omega 3 and omega 6 fatty acids may also contribute to obesity, depression, dyslexia, hyperactivity and even a tendency toward violence.
Bringing the fats into proper proportion may relieve those conditions, says Joseph Hibbeln, M.D., a psychiatrist at the National Institutes of Health and perhaps the world's leading authority on the relationship between fat consumption and mental health. At the 2006 Nutrition and Health Conference sponsored by the University of Arizona's College of Medicine and Columbia University's College of Physicians and Surgeons, Hibbeln cited a study showing that violence in a British prison dropped by 37 percent after omega 3 oils and vitamins were added to the prisoners' diets.
If you follow my anti-inflammatory diet (available on my Web site), you should get a healthy ratio of these fatty acids. In general, however, you can cut down on omega 6 levels by reducing consumption of processed and fast foods and polyunsaturated vegetable oils (corn, sunflower, safflower and soy, for example). At home, use extra-virgin olive oil for cooking and in salad dressings. Eat more oily fish (or take fish-oil supplements), walnuts, freshly ground flaxseed and omega 3-fortified eggs. Your body and mind will thank you.
Sabtu, 24 Mei 2008
Soda Consumption Linked to Heart Disease
Drinking one or more carbonated beverages per day may increase your risk of developing cardiovascular disease, according to a new study published in Circulation, the journal of the American Heart Association."We were struck by the fact that it didn't matter whether it was a diet or regular soda that participants consumed," said lead author Ramachandran Vasan, of the Boston University School of Medicine.
The research was conducted as part of the ongoing Framingham Heart Study, a large-scale, multigenerational study that began in 1948 and continues today with the grandchildren of the original participants. Scientists conducted 9,000 "person observations" of middle-aged women and men over a four-year period.
Participants who consumed one or more sodas daily were 48 percent more likely to have metabolic syndrome than those who consumed less. Among those who did not begin the study with metabolic syndrome, regular soda drinkers were 44 percent more likely to develop the syndrome than those who drank less than one soda per day.
Metabolic syndrome is the name given to a series of linked symptoms that are correlated with a higher risk of cardiovascular disease. Drinking one or more carbonated beverages per day was also correlated with an increase in these symptoms: a 32-percent higher chance of having low HDL levels; a 31-percent higher risk of becoming obese; a 30-percent higher chance of increased waist circumference; and a 25-percent greater chance of having increased blood triglycerides or fasting hyperglycemia.
Senin, 19 Mei 2008
Cholesterol
Blood cholesterol is a risk factor for coronary artery disease and heart attack, so reducing your risk of high cholesterol is a worthy goal.
However, the next time you brag that your cholesterol is nice and low -- or lament that your number is in the mid-200s -- know this:
"Your total cholesterol is a pretty meaningless number," says Maureen Mays, M.D., a preventive cardiologist and lipid specialist at Oregon Health & Science University in Portland.
"Not only does the general public not know this, some doctors don't either."
Here's why "the number" is so misleading.
Total cholesterol is calculated by adding LDL (bad cholesterol), HDL (good cholesterol), and one-fifth of your triglyceride total.
"We have been using this formula of adding a bad thing to a good thing and factoring in one-fifth of a bad thing, and it's not useful," Dr. Mays says.
A smarter way of looking at cholesterol risk is by component.
LDL, or bad cholesterol, is very responsive to good nutrition and exercise. The target number is less than 100 mg/dL. It's not uncommon for LDL to swing up by 40 percent in response to a sedentary lifestyle and a diet high in saturated and other unhealthy fats, according to Dr. Mays.
It can also drop by up to 40 percent in response to a heart-healthy diet and regular exercise.
When should you have a cholesterol test?
One in 500 people has an inherited risk of extremely high LDL and should be put on statins to control their risk of heart disease.
Being overweight can also raise your triglycerides, for which the goal is 150 mg/dL or under.
High triglycerides put you at risk for type 2 diabetes, which is a coronary heart disease risk equivalent; this means that if you have diabetes, you have the same risk of dying from cardiovascular problems as someone who already has coronary heart disease.
While increasing age and stress will slightly change your cholesterol panel, "stopping smoking is the best way to raise your good cholesterol," says Dr. Mays.
It is critical for women nearing menopause to maintain a healthy diet and exercise plan to counteract the effects of estrogen loss.
Because estrogen suppresses LDL levels, women who reach menopause may notice a surge of bad cholesterol, says Denise Janosik, M.D., a cardiologist and professor of internal medicine at Saint Louis University School of Medicine.
Effect of drugs and alcohol
Certain medications, including the steroid prednisone and HIV drugs, can affect your cholesterol panel negatively, so much so that people who are on protease inhibitors for HIV need to be concerned about developing heart disease, according to Dr. Mays.
One to two drinks a day is fine for keeping your cholesterol in check. More than that may raise triglycerides because of the high sugar and calorie content of alcoholic drinks. Alcohol also raises HDL slightly, but this increase in good cholesterol isn't as great as that caused by a healthy lifestyle.
Hypothyroidism, too, can result in skewed cholesterol numbers.
"If you are fatigued and have sudden weight gain, it is good to have a thyroid screening," says Dr. Mays. "If your thyroid isn't working properly, your lipid panel will make no sense."
However, the next time you brag that your cholesterol is nice and low -- or lament that your number is in the mid-200s -- know this:
"Your total cholesterol is a pretty meaningless number," says Maureen Mays, M.D., a preventive cardiologist and lipid specialist at Oregon Health & Science University in Portland.
"Not only does the general public not know this, some doctors don't either."
Here's why "the number" is so misleading.
Total cholesterol is calculated by adding LDL (bad cholesterol), HDL (good cholesterol), and one-fifth of your triglyceride total.
"We have been using this formula of adding a bad thing to a good thing and factoring in one-fifth of a bad thing, and it's not useful," Dr. Mays says.
A smarter way of looking at cholesterol risk is by component.
LDL, or bad cholesterol, is very responsive to good nutrition and exercise. The target number is less than 100 mg/dL. It's not uncommon for LDL to swing up by 40 percent in response to a sedentary lifestyle and a diet high in saturated and other unhealthy fats, according to Dr. Mays.
It can also drop by up to 40 percent in response to a heart-healthy diet and regular exercise.
When should you have a cholesterol test?
One in 500 people has an inherited risk of extremely high LDL and should be put on statins to control their risk of heart disease.
Being overweight can also raise your triglycerides, for which the goal is 150 mg/dL or under.
High triglycerides put you at risk for type 2 diabetes, which is a coronary heart disease risk equivalent; this means that if you have diabetes, you have the same risk of dying from cardiovascular problems as someone who already has coronary heart disease.
While increasing age and stress will slightly change your cholesterol panel, "stopping smoking is the best way to raise your good cholesterol," says Dr. Mays.
It is critical for women nearing menopause to maintain a healthy diet and exercise plan to counteract the effects of estrogen loss.
Because estrogen suppresses LDL levels, women who reach menopause may notice a surge of bad cholesterol, says Denise Janosik, M.D., a cardiologist and professor of internal medicine at Saint Louis University School of Medicine.
Effect of drugs and alcohol
Certain medications, including the steroid prednisone and HIV drugs, can affect your cholesterol panel negatively, so much so that people who are on protease inhibitors for HIV need to be concerned about developing heart disease, according to Dr. Mays.
One to two drinks a day is fine for keeping your cholesterol in check. More than that may raise triglycerides because of the high sugar and calorie content of alcoholic drinks. Alcohol also raises HDL slightly, but this increase in good cholesterol isn't as great as that caused by a healthy lifestyle.
Hypothyroidism, too, can result in skewed cholesterol numbers.
"If you are fatigued and have sudden weight gain, it is good to have a thyroid screening," says Dr. Mays. "If your thyroid isn't working properly, your lipid panel will make no sense."
Minggu, 18 Mei 2008
Supplemental lutein and DHA may help prevent macular degeneration
Macular pigment optical density (MPOD) is a measure of retinal concentrations of lutein and zeaxanthin, two antioxidants acquired from the diet. Docosahexanoic acid (DHA) is an omega-3 fatty acid found in the retina of the eye. New research shows that supplementing with lutein and DHA may help reduce the risk of age-related macular degeneration (AMD) by increasing MPOD.
In a study recently conducted at Tufts University in Boston, researchers randomly assigned 49 women (between 60 and 80 years old) to one of four groups: placebo, DHA (800 mg/d), lutein (12 mg/d), or a combination lutein + DHA supplement. The objective of this four month study was to determine the effects of lutein and DHA on the women's serum concentrations and macular pigment optical density (MPOD).
In all supplement groups, blood nutrient levels were higher at two and four months than at the beginning of the study. DHA supplementation resulted in central increases of macular pigment density, while lutein was associated with eccentric, or away from the center, increases.
Supplementing lutein and DHA may help reduce the risk of age-related macular degeneration by increasing MPOD, helping protect the macula from oxidative damage, and increasing lutein transport into the macula.
Source: The influence of supplemental lutein and docosahexaenoic acid on serum, lipoproteins, and macular pigmentation, Johnson et al, American Journal of Clinical Nutrition, Vol. 87, No. 5, 1521-1529, May 2008
In a study recently conducted at Tufts University in Boston, researchers randomly assigned 49 women (between 60 and 80 years old) to one of four groups: placebo, DHA (800 mg/d), lutein (12 mg/d), or a combination lutein + DHA supplement. The objective of this four month study was to determine the effects of lutein and DHA on the women's serum concentrations and macular pigment optical density (MPOD).
In all supplement groups, blood nutrient levels were higher at two and four months than at the beginning of the study. DHA supplementation resulted in central increases of macular pigment density, while lutein was associated with eccentric, or away from the center, increases.
Supplementing lutein and DHA may help reduce the risk of age-related macular degeneration by increasing MPOD, helping protect the macula from oxidative damage, and increasing lutein transport into the macula.
Source: The influence of supplemental lutein and docosahexaenoic acid on serum, lipoproteins, and macular pigmentation, Johnson et al, American Journal of Clinical Nutrition, Vol. 87, No. 5, 1521-1529, May 2008
Sabtu, 17 Mei 2008
Vitamin D : Many Americans don't get enough of a crucial vitamin
Dr. Michael Holick is one of the foremost authorities on vitamin D. And he's also the man behind a 2007 New England Journal of Medicine article that declared: "It has been estimated that 1 billion people worldwide have vitamin D deficiency or insufficiency."
On Holick's Web site, he notes that vitamin D is "made in the skin as a result of exposure to sunlight." And it's "not a vitamin, but a hormone."
Beyond sun rays, the National Institutes of Health notes that vitamin D is present in, among other things, fatty fish and beef liver. And it's added to items such as fortified milk, juice, yogurt, margarine and ready-to-eat cereal. It also comes in supplement form.
Local nutritionist Cece Davis discovered just how important it is to prevent vitamin D deficiency or insufficiency at a recent nutritionists' conference in Boston, where Holick asked his large audience for a show of hands.
Holick wanted to know how many people in the audience had checked their vitamin D status. Once prompted, about 30 to 40 percent of the audience members raised their hands, Davis recalled. Then Holick asked, "OK, of those people, how many of you were deficient?"
They all raised their hands.
Davis was stunned. After all, these were fellow health experts and, still, they were deficient.
"I was flat amazed at several things," Davis recalled of Holick's speech. "One, how much of a problem it really is and how it is linked to many diseases."
In Holick's journal article, he wrote that vitamin D plays a role in "decreasing the risk of many chronic illnesses, including common cancers, autoimmune diseases, infectious diseases and cardiovascular disease."
Among the causes of vitamin D deficiency Holick cites in his article are inadequate sun exposure; insufficient skin pigment to absorb UVB rays; aging; living above 35 degrees north latitude; obesity and "breast-feeding without vitamin D supplementation."
To prevent vitamin D deficiency, nutrition consultant Nancy Bacon, of the Oklahoma State Department of Health, recommended taking a multivitamin that includes vitamin D, eating vitamin D-rich foods and getting 10 to 15 minutes of sunlight on one's face and arms without sunscreen twice a week. "
However, if you have a family history (of skin cancer) or you are concerned about it, I would not go that route," she said. "I would definitely talk to your physician for specific recommendations."
When it comes to figuring out if a person is vitamin D deficient, Davis said, "The best thing to do is go to the doctor and have a blood test run. ... An alternate method is to assume most of us are deficient and to go ahead and purchase a vitamin D supplement."
Holick wrote, "providing children and adults with approximately at least 800 (international units) of vitamin D3 per day, or its equivalent, should guarantee vitamin D sufficiency unless there are mitigating circumstances."
Later, Holick wrote, "Unless a person eats oily fish frequently, it is very difficult to obtain that much vitamin D3 on a daily basis from dietary sources ... Thus, sensible sun exposure (or ultraviolet B irradiation) and the use of supplements are needed to fulfill the body's vitamin D requirement."
On Holick's Web site, he notes that vitamin D is "made in the skin as a result of exposure to sunlight." And it's "not a vitamin, but a hormone."
Beyond sun rays, the National Institutes of Health notes that vitamin D is present in, among other things, fatty fish and beef liver. And it's added to items such as fortified milk, juice, yogurt, margarine and ready-to-eat cereal. It also comes in supplement form.
Local nutritionist Cece Davis discovered just how important it is to prevent vitamin D deficiency or insufficiency at a recent nutritionists' conference in Boston, where Holick asked his large audience for a show of hands.
Holick wanted to know how many people in the audience had checked their vitamin D status. Once prompted, about 30 to 40 percent of the audience members raised their hands, Davis recalled. Then Holick asked, "OK, of those people, how many of you were deficient?"
They all raised their hands.
Davis was stunned. After all, these were fellow health experts and, still, they were deficient.
"I was flat amazed at several things," Davis recalled of Holick's speech. "One, how much of a problem it really is and how it is linked to many diseases."
In Holick's journal article, he wrote that vitamin D plays a role in "decreasing the risk of many chronic illnesses, including common cancers, autoimmune diseases, infectious diseases and cardiovascular disease."
Among the causes of vitamin D deficiency Holick cites in his article are inadequate sun exposure; insufficient skin pigment to absorb UVB rays; aging; living above 35 degrees north latitude; obesity and "breast-feeding without vitamin D supplementation."
To prevent vitamin D deficiency, nutrition consultant Nancy Bacon, of the Oklahoma State Department of Health, recommended taking a multivitamin that includes vitamin D, eating vitamin D-rich foods and getting 10 to 15 minutes of sunlight on one's face and arms without sunscreen twice a week. "
However, if you have a family history (of skin cancer) or you are concerned about it, I would not go that route," she said. "I would definitely talk to your physician for specific recommendations."
When it comes to figuring out if a person is vitamin D deficient, Davis said, "The best thing to do is go to the doctor and have a blood test run. ... An alternate method is to assume most of us are deficient and to go ahead and purchase a vitamin D supplement."
Holick wrote, "providing children and adults with approximately at least 800 (international units) of vitamin D3 per day, or its equivalent, should guarantee vitamin D sufficiency unless there are mitigating circumstances."
Later, Holick wrote, "Unless a person eats oily fish frequently, it is very difficult to obtain that much vitamin D3 on a daily basis from dietary sources ... Thus, sensible sun exposure (or ultraviolet B irradiation) and the use of supplements are needed to fulfill the body's vitamin D requirement."
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