Lamberts® vitamin d 4000iu provides 100µg of this important nutrient in the preferred d3 form and at a strength that is increasingly being recommended to correct deficiencies. These easy to swallow capsules are made in the uk to pharmaceutical gmp standards. In the uk the only significant food source of vitamin d is oily fish. Most of our vitamin d comes from the sun. But there is a problem: many people in the uk never get what they need from sunlight alone because sunlight’s ability to help us produce vitamin d is hampered by season (it only works in the summer) latitude (the uk is pretty far north) time of day (needs to be between 11am and 3pm) cloud cover (complete cloud cover reduces vitamin d synthesis by 50%) smog/pollution (most of us live in cities) skin melanin content (the darker skinned you are the less vitamin d you’ll get from the sun) and sunscreen (spf of 8 and above). Even in summer when vitamin d is most available it is estimated that 45% of the english population have vitamin d levels of less than 40nmol/l (deficient) and that 75% fail to reach the ‘optimal’ level of 75nmol/l. The natural vitamin d3 in this product is the same form produced by the body when the skin is exposed to sunlight.