Puberty occurs when areas within the brain awaken beginning a cascade of hormone signals which conclude with the gonads (ovaries and testicles) increasing their production of the female and male sex hormones estrogen and testosterone. Under the influence of these hormones a child begins the transition from childhood to sexual maturity. In boys puberty is associated with a growth spurt, the appearance of facial, axillary (arm pit) and pubic hair, acne, deepening of the voice, growth of the testicles and penis while girls undergo a growth spurt, develop breasts, acne, pubic and axillary hair, and growth of the clitoris.
Historical data shows the average age of puberty today is many years sooner than in previous generations. Most experts attribute earlier puberty to better nutrition. A recent article in metabolism.com reviewed how “over-nutrition” accelerates obese children into puberty sooner (referred to as precocious puberty) than normal weight children. The latest studies on causes of precocious puberty suggests that a child’s social environment also exerts an important influence on the timing of puberty. Researchers in Madrid publishing in The Journal of Clinical Endocrinology and Metabolism 95:4305 2010 analyzed the age of puberty in normal children, adopted children and children whose families immigrated (children not adopted but subject to high levels of personal stress) to Spain. Adopted children were 25 times more likely than other groups of children to undergo precocious puberty (breast development before the age of 8 years in girls, and boys under 9 years of age with testicular growth). Over-all girls were 11 times more likely than boys to demonstrate precocious puberty.
Researchers speculate that socio-emotional stresses early in life of children who are later adopted result in changes in the brain that cause premature maturation of vital nerve pathways. This early brain maturation later results in stimulation of the pituitary gland, turning on the hormone pathways that cause puberty. This seems strange to me because various forms of deprivation in childhood can also delay puberty. For example, girls who have anorexia remain child-like in their body development and may fail to menstruate even into their late teens. A decade ago I studied hormone levels in adults during the stress of illness and surgery and found this lowered the sex hormone levels in their blood. This makes sense from an evolutionary point of view because during stressful conditions nature wisely cuts off the reproductive hormones. Why make babies if the environment is hostile in some way? Why the opposite occurs in children under stress of adoption is an interesting but unanswered question.
Gary Pepper, M.D.,
As a culture we donâ€™t plan for a sudden halt in scientific advancements. Our tendency is to expect progress to be rapid and continuous. My prediction is that in certain areas of medical science we are likely to see not only a halt in progress but a slipping backward. In particular, the realm of medical weight management is in complete disarray at this time. Two new drugs designed to induce weight loss have been shot down by the FDA in the last few months. The first is Qnexa, developed by Vivus Inc. Interestingly, Qnexa combines two drugs already approved for use in the U.S. One of the drugs is phentermine which is a medication used for decades as an appetite suppressant. The other is a common drug used to treat seizures with the brand name Topamax (topiramate) which also induces weight loss. The drug performed admirably in clinical trials with most participants losing over 10% of body mass. The FDA cited excessive risks of the drug in its statement of rejection. One wonders why the drugs are still being marketed separately if they are so dangerous.
The latest drug to be rejected by the FDA is Lorgess (lorcaserin), developed by Arena Pharmaceuticals. This drug, not as effective as Qnexa, produced 5% body mass loss in about half of participants in clinical trials. Lab animals showed a tendency to develop breast tumors when exposed to the medication, adding to the FDAâ€™s decision to reject the drug application based on safety concerns.
I am a strong advocate of drug safety and regulation. On the other hand we know obesity, and with it Type 2 diabetes, is epidemic in the U.S. I regard weight loss as the â€œholy grailâ€ when treating type 2 diabetes and yet it is the most difficult goal to achieve. Any drug which could assist in weight loss is highly desirable in the treatment of Type 2 diabetes. Not only does blood sugar improve with weight loss but also blood pressure and cholesterol readings show declines. All three of these parameters are known to be prime contributors to the main cause of death in diabetics, cardiovascular disease.
It has already been 10 years since the last drug was approved specifically for a weight loss indication. The failure of these two latest medications to achieve approval is certain to cause the pharmaceutical industry to severely curtail if not abandon further investment in this type of drug development.
Why is the FDA so reluctant to approve a weight loss pill? This is a complex issue but requires an answer. A new weight loss inducing medication is certain to be highly anticipated and widely prescribed. Therefore, from the very first day of approval the FDA must take responsibility for the well being of millions of people who are likely to take the medication. We are a society which demands our medications deliver miraculous cures with no side-effects. If someone perceives they have been injured by a medication our legal system is primed to unleash brutal retribution on everyone remotely involved in the approval process. Abuse and injury with a medication designed to cause weight loss is almost a certainty. This is a no-win situation for the administration of the FDA.
I predict it will be at least another 10 years before a medication for weight loss is approved by the FDA. Unless there is a change in the climate of litigation in this country it will take longer than that. In the meantime the only new developments in weight loss drugs will be the result of exploiting appetite suppressant effects which are the â€œside-effectâ€ of medications approved for other purposes.
Gary Pepper, M.D.
It seems obvious that cutting away part of the stomach and intestine should cause weight loss. With a smaller stomach and less intestine fewer calories can be absorbed per day causing weight loss. Surgeons who perform gastric by-pass were puzzled however, by how fast their patients showed metabolic improvement after undergoing this procedure. They noticed many of their diabetic patients could be taken off diabetic medication immediately after surgery before weight had been lost. Scientists looking into this phenomena discovered unsuspected ways gastric by-pass improved metabolism.
The intestines produce hormones which regulate blood sugar and appetite. GLP-1 is among the best known of these intestinal hormones. GLP-1 is the basis of a whole new generation of medications used to treat diabetes such as Byetta, Victoza, Januvia and Onglyza. GLP-1 lowers blood sugar, stimulates the pancreas and reduces appetite. After gastric by-pass increased amounts of GLP-1 are produced by the remaining intestine. In a study published in the Journal of Clinical Endocrinology and Metabolism (95:4072-4076, 2010), researchers at St. Lukeâ€™s Hospital in New York discovered that levels of oxyntomodulin, another intestinal hormone that suppresses appetite and acts like GLP-1 on blood sugar levels, is doubled after gastric by-pass.
These exciting discoveries help explain why obese diabetics can often be sent home without any medication to control blood sugar immediately after undergoing gastric by-pass surgery. Although most insurance plans do not cover gastric by-pass surgery, dramatic improvements in patients after the procedure with greatly reduced medication costs may convince insurance companies that paying for the procedure will result in better outcomes and save them money in the long run.
Gary Pepper, M.D.
It’s over between me and Oprah. If you are a regular reader of metabolism.com you probably know about my proposal to Oprah. Don’t get worked up, it wasn’t a marriage proposal. It was a proposal to create a Diabetes Lifestyles reality show for her new cable network. Here’s the background. Oprah is starting her “Own” network on cable and is hosting a contest for ideas to add to her line up. For the past 6 months visitors to Oprah’s website have been able to view all the ideas submitted by the public and vote for their favorite ones. My idea was to produce a Diabetes Lifestyle reality show called This Sweet Life. Over two months my idea acquired about 60 votes and was still in the running. The problem between Oprah and I started when she asked for a commitment. I’m not phobic about commitments but she asked for too much. In order to stay in the contest I had to commit to taking 6 weeks away from my medical practice to go to Los Angles to participate in filming of the conclusion of the contest. I’m sorry Oprah…I’m already committed to my medical practice so you can’t have me!
Maybe some other time. But it was fun while it lasted.
Gary Pepper, M.D., Editor-in-Chief, metabolism.com
Well….we tried. Thanks to everyone who voted for my Diabetes Show idea for the Oprah channel. With only 40 votes so far and 4 days to go, there isn’t much hope of my idea getting recognized by the judges for the Oprah network contest.
I still think it would be great T.V. to have a behind the scenes and personal look at the lives of people with diabetes and their relationships with their health care providers.
Maybe someday I’ll get another opportunity to promote the idea.
Thanks again for those who supported the idea.
Dr. G. Pepper