Is My Daughter At Risk Of Getting Her First Period Early?

Over the last several decades, we have seen the average age of first period (called menarche) decrease by 1-2 years.  The prevalence of girls in USA having early menarche (before age 11) has also increased from 2.6-4.6% to 6.6-12.2% over the last 60 years.  Understanding why periods are starting earlier is important as it can be distressing for these young girls, and is also associated with a higher long term risk of breast cancer, depression, and metabolic risk factors including type 2 diabetes and obesity.

While some of the trend towards earlier periods over the last several decades is due to better health and living conditions, it is also increasingly recognized that environmental factors including weight gain in pregnancy and energy availability during fetal life and early childhood may play an important role. 

A recent review published in Obesity Reviews summarizes the currently available data on this topic.  While it reveals that the literature on this topic is complex, challenging to interpret, and even contradictory at times, the overarching conclusions were that there may be a higher risk of a girl having an early first period when her birth weight is lower, and with higher body weight and weight gain in in infancy and childhood. 

So why would energy availability/energy stores have an influence on age of first period? Here are some possible links:

1. Leptin, which is a signal of energy availability produced by fat tissue, is elevated in obesity, and also in children with low birth weight experiencing catch up growth. Leptin is thought to be necessary for the onset of puberty, so higher leptin may stimulate earlier puberty.

2. Fat tissue converts testosterone to estrogen (and vice versa). Rapid weight gain and childhood obesity is associated with greater production of testosterone derivatives from the adrenal glands, so there may be more of this testosterone available to convert to estrogen in fat tissue, contributing to an earlier first period.

3. Increased insulin levels (as seen in obesity) may advance sexual maturation; in fact, there is some evidence that metformin, a diabetes medication that lowers insulin resistance, may delay onset of periods in low-birth-weight girls with early onset of puberty.

4. Genes have been discovered to be associated with both obesity and age of first period, suggesting there may be some common genetic threads here too.

Also interesting: 

5. Nutritional factors. Breast feeding, and higher intake of plant proteins and fibre may be protective of excessive weight gain and thus protect against earlier periods.  Formula feeding and high intake of cow’s milk and animal protein is associated with an earlier first period (possibly by stimulation of IGF-1 secretion, thus triggering earlier growth).  Higher sugary beverage consumption is also associated with earlier periods, independent of body mass index (BMI).

6. Chemicals in our environment that mess with our hormone systems (called endocrine disruptors) may modify age of first period directly (by modulating hormone responsiveness, epigenetic effects, or stimulating maturation directly), or indirectly by increasing the risk of childhood obesity.

So, it seems that prenatal life, infancy and childhood may present opportunities to improve overall health, and thereby possibly prevent early onset of menstrual periods.  This includes:

• Ensuring appropriate nutritional status of mom while pregnant
• Watching for suboptimal fetal growth (and managing appropriately depending on cause)
• Watching for, and managing, excessive weight gain in childhood
• Watching for signs of early pubertal development and intervening where appropriate with lifestyle/weight management strategies.  I would be very curious to hear from my pediatric colleagues whether they are using metformin in this scenario – please contribute your comments at the end of this blog post!

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www.drsue.ca © 2017

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What Does It Take To Keep Weight Off 6 Years Later?

Understatement: The Biggest Loser is not my favorite show. 

However, the National Institute of Health took this opportunity to learn some things about metabolism after weight loss, and to determine whether changes in food intake or physical activity are associated with keeping the weight off vs regaining weight over the long term.

In a previous blog, we talked about the finding from The Biggest Loser contestants that 6 years after losing weight on the show,  there was about a 500 calorie lower daily calorie burn than what would be expected at their weight 6 years later, which helps to explain why it is so hard to keep weight off after weight loss.

In the most recent publication, we learn that people who were able to keep weight off 6 years after being on The Biggest Loser had higher daily physical activity levels than those who experienced weight regain.  Specifically, those who maintained a weight loss of 25% had increased their physical activity by 160% compared to the start of the study, whereas those who weighed more than they did at the start of the study had increased their physical activity by 'only' 34% (not enough to offset the decrease in metabolism that happens after weight loss). 

Energy intake at 6 years after the show was estimated to be similar between those who maintained weight loss (8.7% less than before the study) vs those who regained weight (still 7.4% less than before the study!). (Scientists: daily energy intake was assumed to be equal to total daily energy expenditure, as weight was reported as stable both at the start of the show, and at the 6 year mark.)

Previous studies such as the LOOK AHEAD study and the National Weight Control Registry have also suggested that people who are able to keep weight off are those who do more physical activity after weight loss, but in these studies, physical activity was self reported (and we know from other studies that physical activity is over reported).  The current study is the first to use the gold standard of doubly labeled water to measure changes in physical activity several years after weight loss.

Bottom Line: While we know that physical activity is not as important for achieving weight loss, the evidence points to physical activity being very important for maintaining weight lost over the long term.

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www.drsue.ca © 2017

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Do Low Fat Diets Prolong Life?

There is hot debate these days as to whether low fat diets are good or bad for us, and whether we have gone overboard in promoting low fat as the way to go in guidelines over the last several decades.

A recent study, published in the British Medical Journal, conducted a systematic review and meta analysis, with their goal actually being to determine whether dietary lifestyle interventions targeting weight loss reduces mortality, cardiovascular disease, and cancer in people with obesity.  They hadn't intended to study low fat diets in particular, but out of the 54 randomized clinical trials that they identified for analysis, all but one of these trials described a low fat diet being included as at least one of their interventions (and all but three trials included some form of exercise advice).  The diets were also usually low in saturated fat.

In this analysis of over 30,000 clinical trial participants in studies of at least 1 year duration, they found that weight loss interventions decreased mortality by 18%, corresponding to 6 fewer deaths per 1000 participants in the studies.  Weight loss after 1 year was 3.4kg (7.5lb), and about 2.5kg (5.5lb) after 2-3 years.

That this study found that dietary interventions reduce mortality in people with obesity is noteworthy, as the amount of weight lost was fairly low, and also because singular diet studies have not shown a reduction in mortality.  In fact, the only obesity studies that have really shown a reduction in mortality are those of bariatric surgery.  It is encouraging that perhaps a mortality benefit from lifestyle intervention emerges when we look at enough people together (as in the current study).

But does this mean that low fat diets are the way to go?   Not necessarily.

It is true that we cannot know if the benefits seen in this study were because of the weight lost, because of the low fat nature of the diets, or a combination of both.

However, a problem with the low fat diet approach in real life (ie outside of a clinical trial) is that it most often results in overconsumption of carbohydrates, which has likely contributed to the increase in obesity that we have seen in the last several decades.  The Mediterranean diet, which is not a low fat diet (fat intake is 35-47% of total calories, with a focus on the healthier unsaturated fats), has been shown to be associated with a reduction in mortality (in systematic reviews and meta analyses of cohort and case control studies). 

We must also remember that all systematic reviews and meta analyses of studies are subject to limitations in interpretation as they are compiling data from a variety of different studies, so they must all be taken with a grain of salt.

BOTTOM LINE: This study suggests that weight reducing diets (which happened to be mostly low fat diets) may reduce mortality.  I would now like to see more studies of diets with moderate carbohydrate restriction and more generous unsaturated fat intake to understand if these diets may have the same benefit.

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www.drsue.ca © 2017

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Does Earlier Menopause Mean A Higher Risk Of Diabetes?

Menopause is a major life transition for women, both psychologically and physiologically.  A number of changes occur in a woman's body that alters metabolism, unfortunately tipping the scales towards an increase in cardiovascular risk.  We know that an earlier age of menopause increases the risk of cardiovascular disease, and that a later age of menopause onset seems to be protective.

Whether earlier age of menopause increases the risk of developing type 2 diabetes has been somewhat controversial; a new study sheds additional light on this question.

The study, published in the journal Diabetologia, evaluated 3639 postmenopausal women from the population based Rotterdam study.  They followed these women for a median of 9.2 years, with the goal of assessing how the risk of developing type 2 diabetes may vary depending on the age of menopause.

They found that the risk for developing type 2 diabetes, compared to women with late menopause (at more than 55 years old), is:

• 3.7 times higher for women with premature menopause (at less than 40 years old)
• 2.4 times higher for women with early menopause (at 40-44 years old)
• 1.6 times higher for women with normal age of menopause (at 45-55 years old)

They found that for every year later that menopause occurred, the risk of developing diabetes decreased by 4%.

So why would the risk of diabetes go up with earlier menopause? With menopause comes a natural decrease in our reproductive hormones (estrogen, progesterone, and testosterone).   These changes promote a loss of muscle and an increase in fat, especially the visceral fat that sits around our abdomen and internal organs - this is the fat that has negative effects on our metabolism.  A loss of progesterone, and hot flashes from having lower estrogen levels, can impair sleep, which is a known risk factor for obesity and metabolic syndrome.  The emotional challenges of menopause may bring out an increase in emotional eating for some women, which can promote weight gain and increase diabetes risk as well.

Interestingly, this study looked at several reproductive hormone levels at the start of the study, and showed that earlier menopause was associated with an increase risk of diabetes, independent of these hormone levels, and also independent of body mass index at baseline or shared genetic factors.

The authors hypothesize that earlier menopause and type 2 diabetes may be a consequence of epigenetic changes, which are changes that alter the physical structure of our DNA.  Epigenetic changes can be caused by a number of factors, including poor diet, smoking, and many other environmental factors. 

Further studies need to be done looking at epigentic changes to determine if these may be responsible for the association between earlier menopause and diabetes risk. If epigentic changes are at play here, living well and healthily throughout life is more important than ever!

After menopause, we can combat cardiovascular and diabetes risk by:

• Keeping active - engage those muscles! This helps to combat the decrease in muscle mass. 
• Making healthy permanent lifestyle changes 
• Having good sleep hygiene
• Getting help from your doctor if you are struggling with menopausal symptoms.

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www.drsue.ca © 2017

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Time To Take ACTION! Barriers To Effective Obesity Care

Despite the fact that obesity is one of the most prominent medical conditions in existence, it is sadly one of the most poorly treated. There exists very little education about obesity for health care providers, and the stigma against obesity is even stronger in the medical community than it is in the general population. Although this is slowly changing, only a small minority of people with obesity actually have this medical condition addressed and treated with the help of their health care provider.

The ACTION study was thus designed to better understand the barriers to effective obesity care. This study was a survey conducted in USA, completed by three groups of people:

• 3,008 people with obesity
• 606 health care providers (primary care/family medicine, internal medicine, and obesity specialists)
• 153 employers who provide health insurance or wellness programs to their employees

Here are some of the key findings: 

1.  While over 80% of health care providers viewed obesity as a chronic disease, only 55% of people with obesity reported receiving an actual diagnosis of obesity. (How can a health care provider move towards treatment of this medical condition if they are not making the diagnosis?)

2. Top 5 reasons that health care providers reported as to why they may not initiate a conversation about weight loss: 

• not enough time
• more important issues to discuss
• they did not believe their patient was motivated to lose weight 
• they did not believe their patient was interested in losing weight (au contraire - data supports that the vast majority of people with obesity are interested in losing weight)
• concern over patient's emotional state or psychological issues

3.  Top 5 barriers to initiating a weight loss effort (agreed to be the same top 5 by people with obesity, health care providers, and employers):

• lack of exercise (note: exercise is less important for weight loss and more important for weight maintenance)
• lack of motivation (could this be because of a lack of understanding of the causes and contributors to each individual's weight struggle?)
• preference for unhealthy food (could this be because food is being used to medicate untreated depression or pain by releasing 'happy hormones' in our brains?)
• controlling hunger
• cost of healthy food

4. Only 24% of people who had a discussion about obesity with their doctor had a follow up appointment scheduled. (Obesity requires long term management - one appointment isn't enough!)

5. Only 17% of people with obesity felt that their employers' wellness offerings were helpful in weight management.


The ACTION study is truly a treasure trove of information that should help all components of  society better identify, understand, and gradually overcome the barriers to successful weight management.

You may be wondering if the results of the ACTION study applies to Canada or other countries, as attitudes and approaches can be very different in different parts of the world.  I'm thrilled to share that the ACTION study is currently underway in Canada (I am on the steering committee for this study) - stay tuned for our results next year. ACTION will be conducted in several countries around the world as well, with deployment planned to begin in 2018.

Disclaimer: The ACTION study is funded by Novo Nordisk, the maker of weight management medication Saxenda (liraglutide 3.0mg).

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www.drsue.ca © 2017

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Anemia, Mortality, and Type 2 Diabetes

Health care providers out there may have noticed that anemia is a not-infrequent finding amongst patients with type 2 diabetes.

It turns out that there are multiple reasons for anemia in type 2 diabetes - and the health consequences may be severe.

A study was recently published evaluating the prevalence, risk factors, and prognosis of anemia in two groups of Australian patients.  They found that the prevalence of anemia was double to triple in people with type 2 diabetes, compared to people without diabetes.

They found multiple risk factors independently associated with a higher risk of anemia, including:

• impaired kidney function: related at least in part to reduced erythropoeitin production by the kidneys, which is a hormone that stimulates red blood cell production
• longer duration of diabetes: 5% increased risk of anemia per year of having diabetes - may be due to decreased red blood cell production and/or increased destruction, as consequences of chronically elevated blood sugar
• metformin use: likely related to vitamin B12 deficiency, but other mechanisms such as low magnesium are considered
• thiazolidinedione use [pioglitazone (Actos) or rosiglitazone (Avandia)]: likely related to fluid retention
• peripheral arterial disease: possibly related to higher oxidative stress, inflammation, atherosclerosis

Other risk factors were identified as well, such as low iron, and low testosterone in men.

After adjustment for other independent predictors of mortality, anemia was associated with a 57% increased risk of mortality over the mean of 4.3 years of study, compared to people with diabetes but without anemia.

The good news is that many of these risk factors for anemia are treatable, and even preventable.  For example: optimizing blood sugar control; checking vitamin B12 in people on metformin; checking iron levels in people who are anemic and investigating for the cause of low iron if so.

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Does Gastric Bypass Surgery Save Lives Only In People With Diabetes?

While we know that weight loss of just 5-10% is associated with an improvement in many parameters of health, the only treatment for obesity that has been suggested to reduce mortality is bariatric surgery.  A new study suggests that if gastric bypass surgery reduces mortality, it may be people with diabetes in particular who enjoy this benefit.

The study, published in Diabetes Care, matched 2,428 people in their database who had gastric bypass surgery by age, BMI, gender, and diabetes status to a control group in the database who had not had surgery.

They found that for the 625 people who had diabetes before gastric bypass surgery, their risk of death from any cause was reduced by 56% at 5.8 years after surgery, compared to people who had diabetes but hadn't had surgery.  In particulary, death from cardiovascular disease, lung disease, and diabetes were lower in the group who had surgery.  The reduction in mortality was the greatest for people whose diabetes went into remission after surgery.

For the 1,803 people who didn't have diabetes before gastric bypass surgery, the risk of death at 6.7 years after surgery was not significantly different than those who didn't have diabetes and didn't have surgery.  When they boiled it down, the risk of death from cancer and lung diseases was lower in the people who had had gastric bypass surgery, but the risk of death from external causes (including injuries, overdose, and suicide) was higher, especially for younger people.

This study is the first to suggest that a reduction in all-cause mortality after gastric bypass surgery may be limited to people who have diabetes before surgery.  However, even if people without diabetes don't enjoy enhanced life expectancy overall, remember that there are still many health benefits to be enjoyed from bariatric surgery.   It's also important to emphasize that this study is retrospective, meaning that researchers looked back in time and analyzed pre existing data.  This type of data can be muddied by other factors that can't be controlled for (called 'confounding factors'), so we have to take them with a grain of salt.

The increased death risk from injuries, overdose, and suicide for people without diabetes who had surgery needs attention. It is known that there is a higher risk of self harm after surgery, pointing towards the need for psychological counselling and support both pre and post surgery.  There is still very little known about how bariatric surgery changes the absorption of medications and other substances, increasing the risk of potential overdose; further studies are desperately needed in this area.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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