High levels of vitamin D in older people can reduce heart disease and diabetes

By | February 16, 2010

High levels of vitamin D in older people can reduce heart disease and diabetes

Middle aged and elderly people with high levels of vitamin D could reduce their chances of developing heart disease or diabetes by 43%, according to researchers at the University of Warwick.

A team of researchers at Warwick Medical School carried out a systematic literature review of studies examining vitamin D and cardiometabolic disorders. Cardiometabolic disorders include cardiovascular disease, type 2 diabetes mellitus and metabolic syndrome.

Vitamin D is a fat-soluble vitamin that is naturally present in some foods and is also produced when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis. Fish such as salmon, tuna and mackerel are good sources of vitamin D, and it is also available as a dietary supplement.

Researchers looked at 28 studies including 99,745 participants across a variety of ethnic groups including men and women. The studies revealed a significant association between high levels of vitamin D and a decreased risk of developing cardiovascular disease (33% compared to low levels of vitamin D), type 2 diabetes (55% reduction) and metabolic syndrome (51% reduction).

The literature review, published in the journal Maturitas, was led by Johanna Parker and Dr Oscar Franco, Assistant Professor in Public Health at Warwick Medical School.

Dr Franco said: “We found that high levels of vitamin D among middle age and elderly populations are associated with a substantial decrease in cardiovascular disease, type 2 diabetes and metabolic syndrome.

“Targeting vitamin D deficiency in adult populations could potentially slow the current epidemics of cardiometabolic disorders.”

All studies included were published between 1990 and 2009 with the majority published between 2004 and 2009. Half of the studies were conducted in the United States, eight were European, two studies were from Iran, three from Australasia and one from India.

via High levels of vitamin D in older people can reduce heart disease and diabetes.

It is best to get a little sun each day, but no sun has been available and I’m still fighting off a cough so I’ve been taking supplements.  I’ve been taking 2,500 IUs of D3 a few mornings a week for a while now.  If you take this much day after day for a month, you’ll probably be okay. Up to 10,000 IUs per day may be the actual safe limits for adults according to one site.  Just watch for symptoms and cut back if you experience any.  To be safe, you may want to stick with 1,000 IUs, since one site says “Chronic ingestion of only 1,600 to 2,000 IU daily of vitamin D is sufficient to cause toxicity.” – link Not sure what study is the source of that last statement or how old it is.

After some more research, I don’t really know how much if any Vitamin D I should be taking. I certainly don’t need any more confusion or heart rhythm abnormalities.

Vitamin D toxicity can cause nonspecific symptoms such as nausea, vomiting, poor appetite, constipation, weakness, and weight loss [88]. More seriously, it can also raise blood levels of calcium, causing mental status changes such as confusion and heart rhythm abnormalities [7].

The use of supplements of both calcium (1,000 mg/day) and vitamin D (400 IU/day) by postmenopausal women was associated with a 17% increase in the risk of kidney stones over 7 years in the Women’s Health Initiative [89].

I think the way to tell is to get tested. The normal range is 30.0 to 74.0 nanograms per milliliter (ng/mL). According to the NIH, the jury is still out on Vitamin D as far as the safe upper limit of supplements.

10 thoughts on “High levels of vitamin D in older people can reduce heart disease and diabetes

    1. Mister Vitamins

      I don’t think 2500 IUs per day of D3 is too much.

      “Currently, the Tolerable Upper Limit is Vitamin D 2000 IU per day. Vitamin D research shows that this ‘upper limit’ of Vitamin D 2000 IU per day SHOULD be the Recommended Daily Allowance – NOT the Tolerable Upper Limit. … In fact, Vitamin D Scientists have come together with this ‘Call to Action’ letter to induce the North American governments to make the use of Vitamin D 2000 IU as the baseline minimum requirement for all healthy adults. … “The conclusion was that the UL (safe upper limit) for vitamin D consumption by adults should be 10,000 IU/d.

      This indicates that the margin of safety for vitamin D consumption for adults is (more than) 10 times any current recommended intakes.”

      -Vieth et al, ‘The urgent need to recommend an intake of vitamin D that is effective’

      Read more: here

      More info from Wikipedia:

      Vitamin D is stored in the human body as calcidiol (25-hydroxy-vitamin D) which has a large volume of distribution and a half-life of about 20 to 29 days.[16] Ordinarily, the synthesis of bioactive vitamin D hormone is tightly regulated, and prevalent thinking is that vitamin D toxicity usually occurs only if excessive doses (prescription forms or rodenticide analogs) are taken.[50] Serum levels of calcidiol (25-hydroxy-vitamin D) are typically used to diagnose vitamin D overdose. In healthy individuals, calcidiol levels are normally between 32 to 70 ng/mL (80 to 175 nmol/L), but these levels may be as much as 15-fold greater in cases of vitamin D toxicity. Serum levels of bioactive vitamin D hormone (1,25(OH2)D) are usually normal in cases of vitamin D overdose.[3]

      The exact long-term safe dose of vitamin D is not known. In 1997 the U.S. Dietary Reference Intake Tolerable Upper Intake Level (UL) of vitamin D for children and adults was set at 50 micrograms/day (2,000 IU)[51], but this is viewed by some researchers as outdated and overly restrictive.[52] A 2007 risk assessment was made by two employees of the dietary supplement trade association Council for Responsible Nutrition,[52] that represents companies including Amway, Bayer AG and GlaxoSmithKline,[53] and their two colleagues, who declared that they had no personal or financial conflicts of interest. They suggested that 250 micrograms/day (10,000 IU) in healthy adults should be adopted as the tolerable upper limit.[52] In adults, sustained intake of 1250 micrograms/day (50,000 IU) can produce toxicity within a few months.[3] For infants (birth to 12 months) the tolerable UL is set at 25 micrograms/day (1000 IU), and vitamin D concentrations of 1000 micrograms/day (40,000 IU) in infants has been shown to produce toxicity within 1 to 4 months. Other sources indicate that the threshold for vitamin D toxicity in humans is 500 to 600 micrograms per kilogram body weight per day.”[54] In rats an oral LD50 of 619 mg/kg is noted.[55] All known cases of vitamin D toxicity with hypercalcemia have involved intake of over 1,000 micrograms/day (40,000 IU)[56].

  1. Vitamin D Deficient

    Vitamin D seems to be in the headlines all the time at the moment. This is a well-respected study by organization who can be trusted, so we should take note of it. However, we’ve must also be careful about the sources of it that we use and also to ensure that our basic diet contains all of the goodness that our bodies require.

    Kind regards,


  2. Type 2 diabetes and heart disease

    Several studies indicate that vitamin d helps. But is need to be established whether its better directly taken from sunlight or as a drug. Also simpler methods need to be evolved to determine current level of vitamin D in humans.

  3. wonderfulflowergarden.com

    High blood levels of vitamins to also include magnesium and calcium. Magnesium is a good vitamin for high blood pressure and that this deficiency can cause blood pressure. It can also be found in green leafy vegetables, nuts, seeds, purslane, poppy seeds and green beans.

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