Why we bond with dogs
Dogs may be man’s best friend, but a new Japanese study suggests that they share a bond with humans that’s more like one between parent and child.
The research team analyzed 30 dog owners and their pets, paying particular attention to eye contact. They found that gazing into each others’ eyes triggers a burst of oxytocin - the hormone that regulates love, nurturing and trust – in the brains of both human and canine. Further, they found that the more eye contact that was made, the more concentrated the level of oxytocin.
To test the results of the study, published in Science, the researchers also looked at animal management professionals who had raised and nurtured wolves. They found that although canines are descendants of wolves, there were no cases of mutual gazes or oxytocin surges between the handlers and wolves. The team also conducted a separate experiment, where dogs were given an oxytocin supplement 30 minutes before interacting with their owners. In female dogs, the supplemental oxytocin increased the number of times the dog would gaze at the owner, increasing brain-oxytocin of the owner. This however, did not occur in male dogs.
The researchers suggest that the study helps us understand how dogs and humans, although different species, can grow to love and protect each other as if they were family members. They say the oxytocin “feedback loop” was a tool in the evolution of dogs, to help them adopt human behavior and form tight bonds for protection.
Kids taught about sexual abuse more likely to report it
A team of researchers from the Queensland University of Technology in Brisbane, Australia, studied 5,802 elementary and high school students from countries around the world to test the value of educational programs in schools. They discovered that 14 in 1,000 students reported sexual abuse when sex abuse programs were offered. When students did not receive sexual abuse prevention programs, only four in 1,00 reported cases of abuse.
The researchers also found that children who did participate in an education program were more prone to try and protect themselves in simulated scenarios involving interaction with strangers.
In-school sexual abuse programs educate students on how to effectively recognize, react and report abuse. Programs would typically educate children on “safety rules, body ownership,” and, recognizing “different types of touch,” as well as the proper person to tell. The researchers compiled data from 24 programs in countries such as China, Germany, Spain and the US for the study, published in the Cochrane Database of Systematic Reviews.
Researchers also noted that the programs did not cause any negative side effects, or increases in anxiety or worry, but advised that the results should be taken “cautiously.” Although some cases showed children remembered what they learned up to six months later, experts criticized that there is no guarantee a child will react the same way in real life as displayed in the class. They stress that simulations don’t reflect the reality of sexual abuse, since most children are abused by someone they know.
Weight loss linked to bone loss
New research suggests that weight loss in middle-age could be linked to bone loss – particularly for women.
Research from Brigham and Women’s Hospital in Boston analyzed data from a large weight loss study which looked at 424 people between the ages of 30 and 70 who were either overweight or obese at the beginning of the study. About 60 percent were women. Participants were randomly assigned one of four low-calorie diets – two of which were considered high-protein, and two of which were considered average amounts of protein.
Participants were given bone density measurements of the spine and hip at the beginning of the study, at six months into the study, and again after two years.
The findings, which were published in The Journal of Clinical Endocrinology and Metabolism, found that men lost an average of eight percent of their body weight, and women lost an average of 6.4 percent. While the weight loss rates were comparable, postmenopausal women also lost spine and hip bone density compared to the men, who actually gained spine and hip bone density. The premenopausal women subjects showed only hip-bone loss.
Additionally, menopausal women that lost abdominal fat (the kind linked to heart disease and diabetes) showed a strong link to bone loss. Bone loss was also linked to the amount of lean muscle mass a person lost. Lean mass is important for supporting skeletal health.
Men lost more fat mass than lean mass compared to women.
Postmenopausal women showed a loss of lean mass and fat mass along with bone density loss.
While more research is needed to better understand the sex differences in bone loss, these findings highlight the importance of protecting skeletal health through weight loss. Weight loss is important and beneficial for a variety of health conditions including cardiovascular health, but women who are trying to lose weight should consider supplementing with calcium and vitamin D to reduce incidental bone density loss.