Dave
Wed, Dec-19-07, 06:15
Canadian researchers are working on a new study which confirms
that people of color--those of African and east Asian
backgrounds--may be dangerously low in vitamin D. Dr. Esteban
Parra and his colleagues at the University of Toronto were
surprised by these deficiencies. Their study was conducted
last winter through blood tests performed on students of the
Mississauga campus at the University of Toronto. The students
were from a variety of ethnic backgrounds.
He asked 106 healthy young adults to report their ancestry and
to keep a diary of everything they ate and all the supplements
they took for a week. He then tested their blood for vitamin
D, which are measured in 25-hydroxyvitamin D (25-OHD) levels.
When testing for Vitamin D, anything above 75 nanomoles per
litre (nmol/L) of 25-OHD is considered optimal. Anything less
than 25 nmol/L is considered seriously deficient, a level at
which the bones go soft (commonly called rickets). A level
between 25 and 50 nmol/L is considered insufficient; but it is
not yet low enough to lead to a deficiency.
Parra and his colleagues found a very high prevalence of
insufficiency. Their first surprise was just how many of the
otherwise healthy students were seriously deficient in vitamin
D during the winter months, when the number of daylight hours
is shortened and when people are less likely to absorb
sunlight through exposed skin.
The big shock came when it was discovered that the darker the
skin of the students, the lower their levels of vitamin D.
Among those of European origin, 34 per cent had insufficient
levels of vitamin D. For those from East Asian or Chinese
descent, 85 per cent had insufficient levels. The students
from South Asia--countries such as India--93 per cent had
insufficient levels And among those of African ancestry, 100
per cent--everyone tested--had insufficient levels. In this
last group, about 43 per cent were considered deficient, with
levels below 25 nmol/L.
Parra says that the reason that the darker-skinned students
had lower vitamin D levels is that darker skin contains a
natural sunblock, making it harder for the skin to produce
vitamin D from the sun. The fact that darker-skinned people
are not as able to absorb is not new, but the results startled
the research team.
"Vitamin D affects lots of aspects of health. I mean there is
the bone but also cancer, and even risk of type 2 diabetes.
These are not minor items," said one author.
A landmark study, released earlier this year, found that a
combination of vitamin D3 and calcium had a substantially
marked effect on reducing cancer incidence. The four-year
study found that women who regularly took vitamin D3 had a 60
per cent reduction in cancer infections compared to a group
taking placebos.
Shortly after the release of that study, the Canadian Cancer
Society issued a recommendation that Canadians take 1,000
International Units of vitamin D during winter months. It also
advised those with darker skin to take 1,000 IU units
year-round.
Dave
Full text article above extracted from
http://shamvswham.blogspot.com/
that people of color--those of African and east Asian
backgrounds--may be dangerously low in vitamin D. Dr. Esteban
Parra and his colleagues at the University of Toronto were
surprised by these deficiencies. Their study was conducted
last winter through blood tests performed on students of the
Mississauga campus at the University of Toronto. The students
were from a variety of ethnic backgrounds.
He asked 106 healthy young adults to report their ancestry and
to keep a diary of everything they ate and all the supplements
they took for a week. He then tested their blood for vitamin
D, which are measured in 25-hydroxyvitamin D (25-OHD) levels.
When testing for Vitamin D, anything above 75 nanomoles per
litre (nmol/L) of 25-OHD is considered optimal. Anything less
than 25 nmol/L is considered seriously deficient, a level at
which the bones go soft (commonly called rickets). A level
between 25 and 50 nmol/L is considered insufficient; but it is
not yet low enough to lead to a deficiency.
Parra and his colleagues found a very high prevalence of
insufficiency. Their first surprise was just how many of the
otherwise healthy students were seriously deficient in vitamin
D during the winter months, when the number of daylight hours
is shortened and when people are less likely to absorb
sunlight through exposed skin.
The big shock came when it was discovered that the darker the
skin of the students, the lower their levels of vitamin D.
Among those of European origin, 34 per cent had insufficient
levels of vitamin D. For those from East Asian or Chinese
descent, 85 per cent had insufficient levels. The students
from South Asia--countries such as India--93 per cent had
insufficient levels And among those of African ancestry, 100
per cent--everyone tested--had insufficient levels. In this
last group, about 43 per cent were considered deficient, with
levels below 25 nmol/L.
Parra says that the reason that the darker-skinned students
had lower vitamin D levels is that darker skin contains a
natural sunblock, making it harder for the skin to produce
vitamin D from the sun. The fact that darker-skinned people
are not as able to absorb is not new, but the results startled
the research team.
"Vitamin D affects lots of aspects of health. I mean there is
the bone but also cancer, and even risk of type 2 diabetes.
These are not minor items," said one author.
A landmark study, released earlier this year, found that a
combination of vitamin D3 and calcium had a substantially
marked effect on reducing cancer incidence. The four-year
study found that women who regularly took vitamin D3 had a 60
per cent reduction in cancer infections compared to a group
taking placebos.
Shortly after the release of that study, the Canadian Cancer
Society issued a recommendation that Canadians take 1,000
International Units of vitamin D during winter months. It also
advised those with darker skin to take 1,000 IU units
year-round.
Dave
Full text article above extracted from
http://shamvswham.blogspot.com/