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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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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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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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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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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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.

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Are Obesity Genetics Written In Stone?

In my practice, I often talk about the genetic predisposition to obesity.

Modern science has now identified over 100 genes that are associated with obesity, with each of these genes contributing a pound or two to the overall weight struggle.  So if a person has a high number of these 'bad' genes, they will have a bigger struggle with obesity, and a higher 'set point' of body weight, than someone who has only a few of these genes.   This can seem like a huge bummer - you can't change your genes (side bar: well actually you can but not in a good way - that's a story for another day) - so does this mean that the efforts to lose weight are hopeless?

The answer is, no.  Even for people who have more of the obesity-engendering genes, it is possible to lose weight, though a realistic weight goal will likely be higher than someone who has less obesity engendering genes.  In addition, a new study sheds light on gene-environment interactions in obesity, teaching us that certain behaviours can modify the effect of our genes on our body weight.

The study, published in PLOS Genetics, looked at gene-environment interactions for body mass index, using a large database of over 350,000 Caucasian people from the UK Biobank.  They found 15 lifestyle factors that influence our genes' effects on body weight, including:

• alcohol intake frequency
• usual walking pace
• socioeconomic status
• number of days per week of physical activity lasting at least 10 minutes
• time spent watching TV
• frequency of climbing stairs
• smoking 

So, the good news here is that we CAN influence our genes' effect on body weight to some extent with the lifestyles we lead. While some of the ability to use these factors may be affected by e.g. physical limitations, I think it's encouraging to know that the effect of our genetics are not set in stone.

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How Successful is Gastric Bypass Surgery 12 Years Later?

We know that gastric bypass surgery is a powerful tool in the management of obesity and metabolic syndrome.  However, there is not a lot of data available following patients out over the very long term.  A recent study is the first prospective study looking only at Roux-en-Y gastric bypass surgery, to give us data out as far as 12 years.

The study, published by Adams and colleagues in the New England Journal of Medicine, enrolled 418 patients in Utah, USA who underwent gastric bypass surgery, and compared them over the long term to 417 patients who wanted surgery but did not have surgery (primarily because of lack of financial insurance coverage), and a third group of 321 patients with obesity who were not interested in surgery. They had an excellent rate of follow up of over 90% of patients at 12 years.

Here are some of the key findings: (skip to take home messages below for the short version)

1.  Weight loss:

• Two years after gastric bypass surgery, the mean weight loss was 45 kg. 
• At 6 years postop, the mean weight loss was 36.3kg (so there was about 20% weight regain, which is very consistent across studies).
• At 12 years postop, the mean weight loss was 35kg – so weight was overall stable from 6 years to 12 years after surgery.

 [At 12 years, people who wanted surgery but didn’t have it had lost 2.9 kg (probably because they were part of this study), and people with obesity who did not want surgery had lost 0 kg (also notable for no weight gain over the long term).]

2.  Type 2 diabetes:

Among patients in the surgery group who had type 2 diabetes before surgery:

• At 2 years postop, 75% of diabetes had gone into remission.
• At 6 years postop, 62% of diabetes cases were in remission
• At 12 years postop, 51% of diabetes cases were in remission.
• The likelihood of diabetes being in diabetes remission at 12 years was 8.9 times higher for those who had had surgery compared to those who wanted but did not get surgery, and 14.8 times higher than those who did not want surgery in the first place.
• At 12 years, the likelihood of being in diabetes remission was highest in people who had diet controlled diabetes before surgery (remission rate 73%), less for people who needed pills to treat their diabetes before surgery (remission rate 56%), and lowest for people who required insulin to treat their diabetes before surgery (remission rate 16%). 
• At 12 years, there was a 91-92% lower risk of having new type 2 diabetes develop in patients who had had bariatric surgery, compared to the non surgery groups.

3.  Mortality rates:

At 12 years, mortality in people who had gastric bypass surgery was lower than those who wanted surgery but didn’t get it, but there no different between those who had gastric bypass surgery than those who didn’t want surgery in the first place, likely because the group not wanting surgery was healthier at baseline. There were 5 suicides in the group that had bariatric surgery, compared to 2 suicides in the non surgical group.  (see here and here and here for discussion of suicide risk after bariatric surgery ) 

Take home messages from this study:

• On average, weight loss is stable over the long term after gastric bypass surgery – though the results can be different for different people, and certainly lifelong dedication to permanent lifestyle changes are essential for continued success.

• Gastric bypass surgery can be a powerful tool to not only put diabetes into remission, but also to decrease the risk of developing diabetes later on.  Earlier intervention is better, because the longer a person has diabetes, the more tired their pancreas gets (ie decreased beta cell function, which are the cells that produce insulin), and a tired pancreas may be too tired to control blood sugars after bariatric surgery without help from medication.  Thus, considering bariatric surgery early in the course of diabetes, or even in the prediabetes phase, may have the most powerful impact.

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Mental Health and Bariatric Surgery - Canadian Data

We know that there is a relationship between mental health and obesity, with mental health issues such as depression being associated with an increased risk of obesity, and with the risk of mental health issues developing increasing as weight increases. In people with more pronounced obesity who are considering bariatric surgery as a treatment option, it is important to consider how mental illness may impact the efficacy and safety of surgical treatment for obesity.

These issues were beautifully summarized in a recent review by Val Taylor and colleagues, published in the Canadian Journal of Diabetes, with a focus on Canadian data.

Here are a few of the highlights:

1. How common are mental health issues in Canadian bariatric surgery patients? 

Over half of patients presenting in Ontario for bariatric surgery had a history of mental illness (most commonly depression). Neither a history of depression nor bipolar disorder seem to be associated with success of weight loss with bariatric surgery, but stability and control of mental health issues preoperatively is important to optimize success.  The prevalence and severity of depression in the bariatric population are consistently decreased after surgery – but there is a risk of development of depression for some people as well, which may be related to some of the psychological challenges that can present after surgery.  Many people with mental health issues are taking medications to treat these conditions, and absorption of these meds may be affected after surgery, so close monitoring to ensure good control of the mental health issue after surgery is important.

2. Eating disorders:

Binge eating disorder (BED) has a prevalence of up to 30% in people presenting for bariatric surgery, with the data conflicting on whether BED reduces the success of weight loss with bariatric surgery. Management of the feeling of loss of control and regulation of emotions in these individuals are important factors to help reducing binge eating in this group.

Active bulimia is a contraindication to bariatric surgery.

3. Suicide risk:

While depression usually improves after surgery, the risk of suicide is increased after bariatric surgery, with a multitude of possible reasons/contributors behind this fact.  The risk of self harm seems to be increased at least 3 years after surgery, so long term psychological follow up and support of bariatric patients is essential.

4. What if there is a past history of sexual abuse?

A history of sexual abuse is present in 21.5% of people in the Ontario Bariatric Surgery Registry.  While this does not appear to influence the success of surgery, these individuals are at a higher risk of mental health issues such as depression, speaking to the need for proper assessment and follow up.

5.  Substance use/abuse:

A history of substance use (alcohol, tobacco, or recreational/illicit drugs) seems to be correlated with a risk of substance use after surgery, particularly if the substance use history is near to the time of surgery.  Alcohol abuse is a particular risk, as alcohol hits harder and fasterafter surgery.  A ‘transfer’ of addictions from one thing to another (eg, from food to gambling) after surgery has been described, and should be discussed and managed ahead of time.

Most often, mental health issues can generally be well managed to optimize success of the individual undergoing bariatric surgery.  Identifying and managing these issues before surgery is essential, and long term support after surgery is key as well.

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Blood Sugar and Insulin Levels As A Biomarker For Weight Loss Success?

To date, no particular diet composition has been shown to be superior to another for weight loss success in the general population.  However, we haven't yet ruled out that some types of diets may work better for certain specific groups of people.  For the first time, a new study suggests that people with prediabetes or diabetes, and people with higher fasting insulin levels, may have better weight loss success with either a lower glycemic load diet, or a diet containing a large amount of fiber and whole grains.

The study, published in the American Journal of Clinical Nutrition, evaluated data from three studies and stratified weight loss results by fasting blood sugar and insulin levels.

The first trial, called the DioGENES study (as blogged previously), looked at the ability to maintain weight loss using a high vs low glycemic index and high vs lower protein diet.   The results of this study overall showed that a low GI, higher protein diet was superior to a high GI, lower protein diet to maintain lifestyle-induced weight loss.  In the current analysis, they found that people with prediabetes regained 5.83kg more on a high GI diet than a low GI diet, whereas people with normal blood sugar regained only 1.44kg more on a high GI diet than a low GI diet.

The second study, called the SHOPUS study, was designed to test the New Nordic Diet, which is high in fiber and whole grains. People with prediabetes lost a mean of 6 kg on this diet, whereas people with normal blood sugars lost only 2.2kg.

Finally, in the NUGENOB study, which was designed to test nutrient-gene interactions in obesity, people with diabetes lost a mean of 2kg more on the high fat/low carb diet than on the low fat/high carb diet, whereas people with normal sugars lost only 0.43kg more on the above comparison.

When the authors incorporated fasting insulin levels into these analysis, the associations above were strengthened further.  Some interesting phenotypes were also revealed:

• people with lower fasting blood sugar and high fasting insulin levels responded equally on all 3 pairs of diets 
• people with high fasting sugars and low fasting insulin levels did better on diets with a lower glycemic load and more fiber and whole grains
• people with lower blood sugar and lower fasting insulin did better on a low fat/high carb diet. 

We often talk about precision medicine - customization of health care decisions based on each individual's genetics, lab results, hormone levels, and so on; yet in obesity medicine, we have very little routinely measured information that can help us determine what type of management program may be best for our patient.  Finally we have some data, using easily measurable blood tests, that may help to guide us.

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Obesity, Addiction, Alcohol and Bariatric Surgery Part II

We know that the factors behind each individual's struggle with obesity are unique, with a long list of physiologic, psychological, and environmental factors as potential contributors.  We are also learning increasingly that there are many areas of neurophysiologic (brain), psychological and behavioral overlap in the realms of obesity and addiction.

In part I of this two-part blog post, we discussed some of the changes that happen after bariatric surgery, as discussed in a recent review.

Now, some threads that weave a connection for some people between obesity and addiction: 

1.  For some people, food is an addictive substance.  People who have high scores on food addiction questionnaires have similar patterns of brain activation as in people with other addictions.  Also, overconsumption of certain nutrients (eg sugar) elicits chemical responses in our brains, similar to those that result from consumption of drugs or alcohol.

Some people think that combatting a food addiction is no different than trying to quit smoking.  But remember, a person who quits smoking can (and ideally will) lead their life without ever touching another cigarette.  But the person battling a food addiction can't stop eating - they have to continue to eat for the rest of their lives, while controlling the addictive component that leads to overeating: a very, very difficult thing to do. 

2.  Some people with obesity have more 'turbo-charged' food reward circuits in their brains, which results in a powerful drive to seek high calorie food.  Obesity can also be accompanied by a reduced brain-driven ability to resist temptation and control impulses to eat, with data suggesting that there is a genetic component to these differences.  After gastric bypass surgery, research has identified some changes in this brain activity, and these changes may be associated with the amount of weight lost after surgery.

Know that feeling of: I am so hungry I don't care what it is it just has to happen RIGHT NOW...?
For some people, this feeling may come only if meals are skipped for many hours, or after a fierce workout.  For others, they may feel like this until their body is at a higher body weight 'set point'.  The level of energy reserves, or time from last meal that contributes to the threshold for this feeling to set in, is very different from person to person.

So for people who have a food addiction, as well as for people who have a more powerful reward circuitry, weight management will be difficult, but not impossible - having a psychologist with professional training in obesity management is an important part of the team to help manage their weight struggles.

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Obesity, Addiction, Alcohol and Bariatric Surgery Part I

We know that the factors behind each individual's struggle with obesity are unique, with a long list of physiologic, psychological, and environmental factors as potential contributors.  We are also learning increasingly that there are many areas of neurophysiologic, psychological and behavioural overlap in the realms of obesity and addiction.  A recent review draws on our knowledge of alcohol use after bariatric surgery to help us understand these connections.

After gastric bypass surgery:

• 9.4% of patients who have had gastric bypass surgery report a period of excessive alcohol intake at some point after surgery
• 7% of patients with no preoperative history of excessive alcohol intake develop a problem after surgery
• middle aged females seem to be at higher risk
• post bariatric surgery addiction problems seem to be fairly specific to alcohol (though addictions to other substances, or activities such as gambling are also seen - see 'addiction transference' below)
• when a person who has had gastric bypass surgery drinks alcohol, there is a faster rise, higher peak, and longer duration of blood alcohol levels 

Interestingly, some people who were frequent alcohol consumers before surgery actually have a decreased enjoyment of alcohol after surgery, which may be mediated by an increase in the gut hormone GLP-1, and a decrease in the hunger hormone ghrelin.

Psychological and social factors can also have a big influence on alcohol consumption after surgery.  As blogged previously, food addiction seeking a new outlet (called 'addiction transference') may be a factor for some people.  A need for a coping mechanism as a person watches their body change after surgery may be involved.   Some may reach for alcohol as a way to manage the complex psychological issues that can arise after surgery. 

Stay tuned for the next blog post, where I'll discuss some of the parallels between obesity and addiction discussed in this review. 

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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Eating for Two? Risks of Too Much - or Too Little - Weight Gain In Pregnancy

Many studies have suggested that too much, or too little, weight gain in pregnancy can be harmful to both baby and mother.  A recent review brings together data from over 1.3 million women, to help us understands what the health risk are of inappropriate weight gain in pregnancy.

First, let's review the recommendations for weight gain in pregnancy.  The recommended amount is based on Body Mass Index pre pregnancy, which is calculated by your weight in kg, divided by your height in metres squared (kg/m2). Note that these numbers apply to single pregnancies only (recommendations are higher for twin, triplets etc).

• BMI less than18.5:  28-40 lbs (about 13-18 kg)
• BMI 18.5-24.9:       25-35 lbs (about 11-16 kg)
• BMI 25-29.9:          15-25 lbs (about 7-11 kg)
• BMI 30 or more:     11-20 lbs (about 5-9 kg)

The review, published in the Journal of the American Medical Association, found that gestational weight gain fell below these guidelines in 23% of pregnancies, and above these guidelines in 47% of the pregnancies studied.

For women not gaining enough weight in pregnancy, there was a 53% higher risk of having a small for gestational age baby, and a 70% increase in the risk of preterm birth.

For women gaining excessive weight in pregnancy, there was an 85% higher risk of having a large for gestational age baby, and a 30% increased risk of needing a C section.

Not only do we know that it is important to manage weight during pregnancy, but optimizing weight prior to pregnancy is important too, as underweight or overweight pre-pregnancy is also associated with adverse outcomes.

If you are pregnant or thinking about becoming pregnant, be sure to speak with your doctor about optimizing weight both before and during pregnancy.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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Could Antacid Medications Affect Blood Sugar Control in Diabetes?

Proton pump inhibitors (PPIs) are medications commonly prescribed to treat heartburn and peptic ulcer disease [eg omeprazole (Losec), pantoprazole (Pantoloc), esomeprazole (Nexium), lansoprazole (Prevacid), rabeprazole (Pariet)].    Since PPIs work by blocking acid secretion in the stomach, and since a higher acid content of food lowers its glycemic index, I was asked whether PPIs could increase the effective glycemic index of a meal and thus have a negative impact on diabetes control.

It turns out that PPIs have a very interesting relationship with pancreatic function and blood sugars.

Firstly, as PPIs work by blocking acid secretion in the stomach,  PPIs do increase the pH in the stomach and very high up in the small intestine (proximal duodenum).  However, there is little to no effect on pH in the majority of the small intestine, where carbohydrates are absorbed.

PPIs raise serum levels of a hormone called gastrin, which is responsible for stimulating acid secretion in the stomach.  This is because the gastrin secreting cells in the stomach sense that acid production is low, so more gastrin gets cranked out in an attempt to increase acid secretion.

Interestingly, gastrin stimulates glucose-induced insulin secretion from the beta cells of the pancreas.  There is also some experimental evidence that gastrin may stimulate the production of new beta cells.   Further, PPIs slow emptying of the stomach, because less acid in the stomach means that it takes longer for solid food to be broken down and be ready to pass into the small intestine.

So, based on these mechanisms, it seems that PPIs could possibly have a benefit to blood sugar levels.  While the studies on this are still quite limited, the available evidence suggests that PPIs could lower A1C (a marker of diabetes control) by 0.5% to as much as 1% - possibly as much as a diabetes medication!

PPIs are medications that have benefits but also potential risks, including increased risk of gastrointestinal infections, malabsorption of important micronutrients like calcium, magnesium, vitamin B12, and iron, increased risk of fracture, changes in gut bacteria, and others (note this list is not exhaustive), and they should not be prescribed for the purpose of blood sugar control.

That being said, I will be watching blood sugar control with extra interest the next time one of my patients with diabetes is started on a PPI for their gastrointestinal issues.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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