However, closer examination revealed differences between men and women in two key components of the immune system - T-cells, which protect the body from infection, and B-cells, which secrete antibodies.

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Without intrinsic factor, vitamin B-12 can't be absorbed and leaves your body as waste.

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Some experts have suggested that it may be more effective to supplement the minerals such as zinc and selenium that the body uses to produce catalase, MSR A and B, and tyrosinase, rather than take them directly.

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Vitamin D is incorporated in the body when skin is exposed to sunlight of a certain wavelength but in the UK, during winter months, UV-B radiation can be insufficient to properly support vitamin D synthesis in the body.

BBC: Pregnant women 'ignoring vitamin D advice'

Body piercing performed under nonsterile conditions has been linked to infections such as hepatitis B and C viruses as well as HIV.

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These B-cells produce the hormone insulin that regulates the way sugar is broken down in the body.

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But Harvard stayed financially healthy during the lean years of the Depression partly by enlarging its undergraduate student body--two dynamic presidents during that period, A. Lawrence Lowell and James B.

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