Posts tagged with "Bone strength"

Dark secret: Low levels of vitamin D in elementary school could spell trouble in adolescence

August 21, 2019

Children who play outside gain more than social and athletic skills: There really is such a thing as a “sunny disposition,” according to researchers at the University of Michigan.

A study of school children in Bogotá, Colombia, indicates that the “sunshine vitamin”—vitamin D—not only supports bone health, but also encourages a healthy outlook.

In the study, children with blood vitamin D levels suggestive of deficiency were almost twice as likely to develop externalizing behavior problems during adolescence—aggressive and rule-breaking behaviors—as reported by their parents, compared with children who had higher levels of the vitamin.

Also, low levels of the protein that transports vitamin D in blood were related to more self-reported aggressive behavior and anxious/depressed symptoms. The associations were independent of child, parental and household characteristics.

“Children who have vitamin D deficiency during their elementary school years appear to have higher scores on tests that measure behavior problems when they reach adolescence,” said Eduardo Villamor, a professor at the U-M School of Public Health and senior author of the study appearing in The Journal of Nutrition.

Villamor said vitamin D deficiency has been associated with other mental health problems in adulthood, including depression and schizophrenia, and some studies have focused on the effect of vitamin D status during pregnancy and childhood. However, few studies have extended into adolescence, the stage when behavior problems may first appear and become serious conditions.

In 2006, Villamor’s team recruited 3,202 children aged 5-12 years into a cohort study in Bogotá, Colombia, through a random selection from primary public schools. The investigators obtained information on the children’s daily habits, maternal education level, weight and height, as well as the household’s food insecurity and socioeconomic status. Researchers also took blood samples.

After about six years, when the children were 11-18 years old, the investigators conducted in-person follow-up interviews in a random group of one-third of the participants, assessing the children’s behavior through questionnaires that were administered to the children themselves and their parents. The vitamin D analyses included 273 of those participants.

While the authors acknowledge the study’s limitations, including a lack of baseline behavior measures, their results indicate the need for additional studies involving neurobehavioral outcomes in other populations where vitamin D deficiency may be a public health problem.

According to WebMD, sun exposure is an easy, reliable way for most people to get vitamin D. Exposure of the hands, face, arms, and legs to sunlight 2-3 times a week for about one-fourth of the time it would take to develop a mild sunburn will cause the skin to produce enough vitamin D. The necessary exposure time varies with age, skin type, season, time of day, etc. Just 6 days of casual sunlight exposure without sunscreen can make up for 49 days of no sunlight exposure. Body fat acts like a kind of storage battery for vitamin D. During periods of sunlight, vitamin D is stored in fat and then released when sunlight is gone.

Research contact: villamor@umich.edu

No bones about it: Age at puberty could affect skeletal strength

August 12, 2019

A study recently conducted at the University of Bristol in the United Kingdom has linked the bone strength of teenagers and young adults to the age at which they reached puberty.

Published on August 9 in the open access medical journal,  JAMA Network Open, the research examined six repeated bone scans from 6,389 children who participated in Bristol’s Children of the 90s study between the ages of ten and 25 to assess if the timing of puberty had any influence on bone density throughout adolescence and into early adulthood.

They found that, although teens who had their pubertal growth spurt later than their peers did catch-up to some degree, they continued to have lower bone density than average for several years into adulthood.

Peak bone mass at the end of the teenage growth spurts is considered to be an indication of later risk of fracture and osteoporosis. Lead author and Senior Research Associate in Epidemiology Dr. Ahmed Elhakeem said, “Our research adds to the evidence that children who mature later may be at increased risk of fractures as they grow. They may also have increased risk of the fragile bone condition osteoporosis in later life.”

“Thanks to the ‘Children of the 90s study,’ we were able to look, for the first time, at children in great detail as they grow into young adults and observe their bone density. I’d like to see more advice available for people who reach puberty later on measures they can take to strengthen their bones.

He added, “The next steps should involve more detailed assessments of the long-term effects of puberty on growth and bone development.”

Alison Doyle, head of Operations and Clinical Practice at the Royal Osteoporosis Society, said, “This is important research that adds to a current gap in the evidence of understanding how bone density changes from puberty into early adulthood …. “The charity’s Osteoporosis and Bone Research Academy, which launched earlier this year, is working to build on these findings and create a future without osteoporosis.”

The study did not make conclusions on any influence of the final adult height on the findings. As the study participants are still only in their twenties, follow up with them as they age will be important to reach conclusions about fractures in later life.

Research contact: julia01.walton@bristol.ac.uk