Can smoking marijuana reduce your chances of developing diabetes?
A U.S. study found that people who imbibe regularly had fewer risk factors for the disease than those who don't smoke it. Indeed, marijuana users appeared to have better blood-sugar control than abstainers.
The findings are based on group of adults who took part in the National Health and Nutrition Survey that was carried out between 2005 and 2010 by the U.S. Centers for Disease Control. A total of 4,657 people answered a drug-use questionnaire. Of those participants, 579 were current users, 1,975 were former marijuana smokers and 2,103 had never inhaled pot.
The participants also underwent a series of medical tests that included providing blood samples in the morning after a nine-hour fast, which provides valuable clues about a person's blood-sugar control.
All this data was analyzed by researchers – led by Elizabeth Penner of the University of Nebraska – who looked for such diabetes risk factors as insulin sensitivity among the study participants.
Insulin is a hormone that moves glucose (or sugar) from the bloodstream and into cells where it is used for energy. In a healthy individual, "the amount of insulin that is secreted from your pancreas varies in order to keep your blood sugar at a nice steady level," explained the senior author of the study, Dr. Murray Mittleman at the Beth Israel Deaconess Medical Center in Boston.
But those with Type 2 diabetes don't make enough insulin or their bodies don't respond properly to the hormone – a condition known as insulin resistance. If a person is headed down the road to diabetes, some warning signs will show up in an analysis of a blood sample taken after a prolonged period of not eating.
The study revealed that participants who used marijuana in the previous month had, on average, 16 per cent lower fasting insulin levels than participants who never consumed cannabis. That essentially means that regular marijuana smokers use insulin more efficiently than non-smokers.
The researchers also looked at other measures, such as hemoglobin A1c which can be used for assessing blood-glucose control. The marijuana consumers tended to have more favourable readings.
Furthermore, the study, published Wednesday in the American Journal of Medicine, showed that marijuana users had smaller waist circumferences and higher levels of good cholesterol than the non-users. A big belly is another major risk factor for type 2 diabetes.
So do these results mean that getting high on marijuana will significantly reduce your odds of getting diabetes? It's way too soon to jump to that conclusion based on a single study said Mittleman. But, he added, "the metabolic changes that we are observing are the sorts of things that are favourable with respect to indicating a lower risk of developing diabetes."
Marijuana, once vilified as an illicit weed, is increasingly seen for its medicinal benefits. Its active ingredient, tetrahydrocannabinol or THC, is being used to treat pain, the side-effects of chemotherapy, AIDS-induced anorexia, nausea and other medical conditions.
And, for reasons that researchers cannot yet explain, marijuana consumption is associated with some health outcomes that seem almost unbelievable. Several studies, for instance, have found "marijuana users tend to be more lean than non-users despite the fact they have a higher caloric intake on average," said Mittleman.
Cannabis has a downside, however. Mittleman noted that a study he co-authored several years ago found that marijuana can be bad for the heart – at least briefly. "Immediately after smoking marijuana there is a transient spike in the risk of a heart attack."
That short-term risk could be related to "inhaling plant combustion products" rather than receiving a sudden blast of THC. "Whether it is the drug itself – the active ingredients of marijuana – or whether it is the fact that it is being smoked, isn't entirely clear and there aren't many studies that have looked at other forms of using the drug," such as in a pill.
Mittleman believes it's time for more cannabis research – especially because marijuana is now being consumed by older individuals who may suffer from underlying heart conditions.
"Over time, the age distribution of users has changed. In the past, it was used mostly by young people who had very low risks of cardiovascular problems and other chronic diseases. That has shifted and we have a larger population of older individuals who continue to use marijuana."
Mittleman expects the ranks of older smokers will continue to swell, particularly in the U.S. where more state governments are legalizing marijuana for either medical or recreational purposes.