Maternal deficiencies may be the cause of overt bone disease from before birth and impairment of bone quality after birth. The primary cause of congenital rickets is
vitamin D deficiency in the mother's blood. Congenital rickets may also be caused by other maternal diseases, including severe
osteomalacia, untreated
celiac disease,
malabsorption,
pre-eclampsia, and
premature birth.. Prenatal care includes checking vitamin levels and ensuring that any deficiencies are supplemented. Exclusively breast-fed infants may require rickets prevention by vitamin D supplementation or increased exposure to sunlight. In sunny countries such as Nigeria, South Africa, and Bangladesh, there is sufficient endogenous vitamin D due to exposure to the sun. However, the disease occurs among older toddlers and children in these countries, which in these circumstances is attributed to low dietary calcium intakes due to a mainly cereal-based diet. Those at higher risk for developing rickets include: •
Breast-fed infants whose mothers are not exposed to sunlight • Breast-fed infants who are not exposed to sunlight • Breast-fed babies who are exposed to little sunlight • Adolescents, in particular when undergoing the
pubertal growth spurt • Any child whose diet does not contain enough vitamin D or calcium Diseases causing soft bones in infants, like
hypophosphatasia or
hypophosphatemia, can also lead to rickets.
Strontium is allied with calcium uptake into bones; at excessive dietary levels, strontium has a rachitogenic (rickets-producing) action.
Sunlight Sunlight, especially ultraviolet light, lets human skin cells convert vitamin D from an inactive to an active state. In the absence of vitamin D, dietary calcium is not properly absorbed, resulting in
hypocalcaemia, leading to skeletal and dental deformities and
neuromuscular symptoms, e.g., hyperexcitability. Foods that contain vitamin D include butter, eggs, fish liver oils, margarine, fortified milk and juice,
portabella and
shiitake mushrooms, and
oily fishes such as
tuna,
herring, and
salmon. A rare
X-linked dominant form exists called vitamin D-resistant rickets or X-linked hypophosphatemia. Cases have been reported in Britain in recent years of rickets in children of many social backgrounds caused by insufficient production in the body of vitamin D because the sun's ultraviolet light was not reaching the skin due to use of strong
sunblock, too much "covering up" in sunlight, or not getting out into the sun. Other cases have been reported among the children of some ethnic groups in which mothers avoid exposure to the sun for religious or cultural reasons, leading to a maternal shortage of vitamin D, and people with darker skin need more sunlight to maintain vitamin D levels. Rickets had historically been a problem in
London, especially during the
Industrial Revolution. Persistent thick fog and heavy industrial smog permeating the city blocked out significant amounts of sunlight. It is sometimes known "the English Disease" in some foreign languages (e.g. German: , Dutch: , Hungarian: , Swedish: ). But rickets was prevalent in other cloudy cities as well. Nineteenth-century autopsy studies in Boston, Massachusetts, and Leiden, The Netherlands, showed that 80–90 percent of children had varying degrees of rickets.
Skin color theory Rickets is often a result of vitamin D3 deficiency. The correlation between human skin color and latitude is thought to be the result of positive selection to varying levels of solar ultraviolet radiation. Northern latitudes have selection for lighter skin that allows UV rays to produce vitamin D from 7-dehydrocholesterol. Conversely, latitudes near the equator have selection for darker skin that can block the majority of UV radiation to protect from toxic levels of vitamin D, as well as skin cancer. An anecdote often cited to support this hypothesis is that Arctic populations whose skin is relatively darker for their latitude, such as the Inuit, have a diet that is historically rich in vitamin D. Since these people acquire vitamin D through their diet, there is no positive selective force to synthesize vitamin D from sunlight. Environment mismatch: Vitamin D deficiency arises from a mismatch between an individual's previous and current environment. This risk of mismatch increases with advances in transportation methods and increases in urban population size at high latitudes. Similar to the environmental mismatch when dark-skinned people live at high latitudes, Rickets can also occur in religious communities that require long garments with hoods and veils. These hoods and veils act as sunlight barriers that prevent individuals from synthesizing vitamin D naturally from the sun. In a study by Mithal et al., vitamin D insufficiency of various countries was measured by lower 25-hydroxyvitamin D. 25(OH) D is an indicator of vitamin D insufficiency that can be easily measured. These percentages should be regarded as relative vitamin D levels, and not as predictive evidence for the development of rickets. Asian immigrants living in Europe have an increased risk of vitamin D deficiency. Vitamin D insufficiency was found in 40% of non-Western immigrants in the Netherlands, and in more than 80% of Turkish and Moroccan immigrants. The Middle East, despite high rates of sun-exposure, has the highest rates of rickets worldwide. This fact can be explained by limited sun exposure due to cultural practices and lack of vitamin D supplementation for breast-feeding women. Up to 70% and 80% of adolescent girls in Iran and Saudi Arabia, respectively, have vitamin D insufficiency. Socioeconomic factors that limit a vitamin D-rich diet also play a role. In the United States, vitamin D insufficiency varies dramatically by ethnicity. Among females aged 70 years and older, the prevalence of low serum 25(OH) D levels was 28.5% for non-Hispanic whites, 55% for Mexican Americans, and 68% for non-Hispanic blacks. Among males, the prevalence was 23%, 45%, and 58%, respectively. A systematic review published in the
Cochrane Library looked at children up to three years old in Turkey and China and found a beneficial association between vitamin D and rickets. In Turkey, children who received vitamin D had only a 4% chance of developing rickets compared to children who received no medical intervention. In China, a combination of vitamin D, calcium, and nutritional counseling was linked to a decreased risk of rickets. Parents can supplement their nutritional intake with vitamin D enhanced beverages if they feel their child is at risk for vitamin D deficiency. A 2019 review linked rickets disease to exclusive consumption of
Neocate baby formula. ==Diagnosis==