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Background
In the past 10-15 years, thinking on calcium supplementation has shifted significantly. In 2001, a National Institutes of Health (NIH) Consensus Development Panel on Osteoporosis made the recommendation that calcium should be supplemented to maintain daily intake 1000 - 1500 mg/day in older adults. The reasoning behind this was that calcium is ...
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Short answer: No.
Longer answer: UVB rays are essential for Vitamin D synthesis. According to some studies, 1 hour of sunshine is needed even in sunny climates - but only in average, still depending on latitude, skin color and other factors - to prevent Vitamin D deficiency. Still, even the average sun exposure in mid-latitude regions summers might not ...
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The exact value depends on a lot of things - skin tone, the time of day, latitude, how deep the shade is,...
The study Vitamin D effective ultraviolet wavelengths due to scattering in shade found that the UVB radiation at 280–320 nanometers that is needed for vitamin D production dropped to levels at around 50% in a tree shade and under an umbrella. It ...
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Vitamin D is produced in the skin, not the eyes.(1)
I would imagine that when those indigenous peoples were introduced to sunglasses, they were also introduced to a number of other items they had never previously known, such as tobacco, alcohol and fast food. Diseases they had no immunity to might also have played a role.
The synthesis of vitamin D is ...
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Overloading on vitamin C won't cause death. At around 1000 mg, you will probably have nausea, diarrhea, and stomach aches. 2000 mg is the daily limit, and if you get that high, you will experience more severe side-affects such as severe headaches, vomiting, heartburn, insomnia, and even kidney stones. You probably shouldn't have that much vitamin C, so if ...
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Vitamin C (ascorbic acid - an antioxidant and reducing agent) is water soluble (so dietary excesses not absorbed), and excesses in the blood rapidly excreted in the urine. It exhibits remarkably low toxicity , however LD50 in humans remains unknown given lack of any accidental or intentional poisoning death data.
Government recommended intake:
United ...
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The medical way to ask your question is "What are the pharmacokinetics of pyridoxine (B6 version that you're likely to take)?"
Then that brings us to both primary and secondary sources, along with a good animal model study.
"The greatest portion reaches the brain" will likely be shortly after the peak serum concentration, or Cmax. The amount of time it ...
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Iodine is absolutely an essential mineral, and is required for proper functioning of your body. It is a component of the thyroid hormone triiodothyronine (also known as T3) and its precursor form T4 (thyroxine). This hormone is involved in quite a few processes in the body, and acts on nearly every cell in it.
A deficit of iodine can cause a number of ...
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What you are asking about is called bioavailability, which is the term for how much of a consumed substance is actually taken up by the body, and bioequivalence, which is about whether two products are used the same way in the body.
Protein
For protein, bioavailability is also called Biological Value (BV). The BV of an egg, for example is somewhere around ...
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So it's important to separate cravings/specific hungers from taste.
One's body should, to some degree be able to adjust it's specific hungers to meet it's dietary needs. This one area where our larger brains come with a catch 22. While being smarter and aware allows us to feed ourselves better, we also can ignore or improperly process the bodies attempt ...
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About 1/4 - it varies with the reflectivity of the surface, and angle of the sun. Detailed study is at http://www.ncbi.nlm.nih.gov/pubmed/20199222
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Unless you are very short, your weight indicates that you are severely underweight, see here for details. If you are indeed underweight, then you should follow the advice given there:
If you are concerned about being underweight, please seek a trained healthcare provider.
The general advice that comes second to whatever your doctor's advice is, is given ...
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Only two things affect the synthesis of vitamin D, and those are the amount of UVB photons penetrating the skin and the person's age. See my previous answer for an explanation and citations.
So if we disregard age the only question becomes do light boxes supply adequate UVB to synthesize adequate vitamin D? From what I can tell from a review of the products ...
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There are two important types of vitamins.
Fat soluble and Water Soluble.
Your body will store fat soluble vitamins but will discard excess water soluble vitamins in your urine. Because of this fat soluble vitamins carry a greater risk of toxicity while water soluble carry a greater risk of deficiency.
Some examples of fat soluble 1
A, D, E, K
and water ...
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Unless you're doing something stupid like eating polar bear liver, hypervitaminosis A is the result of long-term overconsumption: taking one supplement in the morning and one in the evening is no more or less dangerous than taking both at once.
According to the National Institutes of Health, the level of vitamin A overconsumption that presents a long-term ...
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No
Skin damage is irreversible. The only thing you can do is make sure your skin is not damaged in the first place.
Skin damage is caused by a variety of factors, but by far the most important one for most people is UV exposure. The primary source of UV is the Sun, but tanning booths may be a significant factor for some people.
While sun burn causes an ...
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Is there an objective answer to whether or not taking a multi-vitamin dietary supplement is beneficial to health?
No, there is not.
If you dig into the existing research, unless you are looking to experience some confirmation bias one way or the other, you will only continue to find evidence that there is no conclusion.
In this case Wikipedia actually ...
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You can't reverse the skin damage, but you can treat wounds and burns, so your skin cell can regenerate faster.
Eating food full of antioxidants and vitamin C, such as blueberries, tomatoes, and cherries can reduce the body’s need for fluids, lowering only the risk for dehydration (study).
If you have a skin sunburn, here are few advices:
Do not pick, ...
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Couldn't find any articles directly looking at effervescent tablets and dental problems, so I took a more broad look and searched for citric acid's effect on teeth.
The combination of citric acid and sodium bicarbonate are routinely used in effervescent tablets designed for human consumption (according to Wikipedia ;).
Citric acid is commonly found in many ...
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To increase weight and be healthy eat plenty of food rich in proteins (black beans, chickpeas, broccoli, potatoes, mushrooms), carbohydrates (Whole grain bread, pasta, cereals) and fat (avocado, olive oil, almonds, walnuts); include supplements and multivitamins in your diet, lift weights (don't do running or cardio) and plan your diet according to your ...
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There doesn't seem to be any evidence of harmful effects of canola oil.
The Mayo Clinic site states :
Health concerns about canola oil are unfounded. Canola oil, which is extracted from the seeds of the canola plant, is generally recognized as safe by the Food and Drug Administration.
Misinformation about canola oil may stem from the fact that the ...
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Nicely, sunlight is best. While we are still not knowing nearly enough concerning all the details, that's a safe bet. Even the supplement lobby acknowledges that:
Despite the increased risk of non-melanoma skin cancers, the Vitamin D Council recommends moderate sun exposure and 5,000 IU of vitamin D3 on days you do not get sun exposure. We are not alone. ...
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Here are few aspects of high-dose vitamin C supplements.
The upper limit(UL) 2,000 mg for vitamin C is not some sort of recommendation, but a dose, which, if exceeded, can cause nausea and diarrhea, for example.
Does it make sense to take vitamin C supplements?
Vitamin C supplements can correct vitamin C deficiency and improve the absorption of iron from ...
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Vitamins and minerals from foods an supplements taken simultaneously can be absorbed normally, because their absorption is usually not regulated by the amounts you take. However, the absorption of iron depends on your body iron stores: the more stores, the less efficient absorption. Still, both acute and chronic iron poisoning is possible with large amounts ...
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This might be true for some substances and false for others. For example, might be true for beta-carotene:
Soluble fiber may inhibit ß-carotene absorption; therefore, consumption of juice may increase plasma ß-carotene concentrations more than whole fruits/vegetables in free-living populations.
Although,
(...) most of this research was conducted in ...
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The quantitive figures for Vitamin A overdose are well established, and widely published.
The RDI in the United States (Different countries may have different values) is 900 micrograms for men, and 700 micrograms for females. 900 micrograms is approximately 3000 IU.
The acute toxic dose of vitamin A is 25,000 IU/kg, and the chronic toxic dose is 4000 IU/kg ...
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No, there is no evidence in reputable sources that any diet can restore a partially removed tooth to a full tooth again.
Any source you do encounter which proposes such a possibility is highly likely to benefit from such a claim (i.e. there exists a conflict of interest between the claim and the truth.)
There is, however, a large body of sound research on ...
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This could be linked to your diet, but Vitamin D is not found in many foods (with the exception of fish and fortified foods). However, there have been some reports that laboratories may be producing an incorrect value.
"This means that compared with the actual concentration of 25(OH)D in a sample of blood serum, a falsely low or falsely high value may be ...
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I found an expert answer for your question. May be this will help you to take right decision.
NDTV Doctors:
"There is no harm in taking a combination of B-complex vitamins with
zinc but there is no evidence that such products have any utility in
controlling loss of hair. Please do not rely on reports in the lay
press because they are not always ...
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According to a couple of systematic reviews of studies, there is insufficient evidence about the lowering effect of vitamin D on blood cholesterol levels.
Vitamin D, Evidence Mayo Clinic (data from Natural Standard Research Collaboration)
Many studies have looked at the effects of vitamin D alone or in
combination with other agents for high cholesterol,...
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