Is Resveratrol Good For Me?

You may just be kicking back with a good glass of Merlot to read my blog this evening, with the thought that you are doing your body a favour by choosing red wine over, say, a bottle of beer.  The reported benefits of red wine have often been attributed to resveratrol.  'Naturally' (haha), the supplement industry has jumped all over this, and now markets resveratrol supplement.  Resveratrol is touted as having a whole list of benefits... but is it really good for us?

Resveratrol is a natural phenol which is actually found not only in grapes, but also blueberries, raspberries, and peanuts.  The highest readily available quantities per serving are found in grape juice or red wine.   Resveratrol got some attention with the discovery that moderate consumption of red wine (1-2 glasses (5oz each) per day) may be associated with a decreased risk of heart disease, and since then, high doses of resveratrol (in supplement form) has been touted to carry a number of health benefits, including a decreased risk of cancer, improved diabetes control, neurological benefits, and even benefits to the skin.

While the evidence overall seems to suggest that red wine is associated with a decreased risk of cardiovascular disease, the reasons for this are not clear. Red wine increases levels of good cholesterol (HDL), but it's not clear if it's the resveratrol, or flavonoids in red wine, or something else that brings these benefits.

As for the remainder of the long list of supposed health benefits of resveratrol - these are far from being proven.  A systematic review was undertaken a few years ago (which is the best way to look for evidence when there are only a smattering of studies otherwise), stating that the published evidence was not strong enough to recommend resveratrol beyond the dose that is found in dietary sources.

In terms of side effects, they found that there was no valid data on the the toxicity of chronic intake, and that the main known side effect of high doses of resveratrol is a laxative effect.  Since then, a small randomized controlled clinical trial was recently published suggesting that resveratrol supplements had no benefit on any aspect of metabolic syndrome, and that high dose resveratrol actually had detrimental effects on cholesterol.

As for any supplement, in an industry which is very loosely regulated (and I use the term 'regulated' loosely at that), there is a huge amount of variation in the amount of resveratrol that one might actually get in a particular supplement.  Purity varies as well, with the supplements containing other chemicals with unknown effects on human health.

Bottom Line: We find resveratrol in the same camp as most other natural remedies - there is insufficient data to suggest a benefit of taking high doses (supplements) to human health, and we don't know about the safety of doing so.

As for getting resveratrol from red wine: It is not recommended to begin alcohol consumption for health reasons, as alcohol has many dangers and toxicities associated with it as well.  For those who do enjoy a small amount of alcohol, it seems that red wine may be a good choice.  See Canada's Low Risk Alcohol Drinking Guidelines for more information on what is considered to be safe in terms of alcohol consumption.

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www.drsue.ca © 2017

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Could Artificial Sweeteners Cause Weight GAIN?

While artificial sweeteners have previously been touted as an excellent way to replace sugar in your diet and help with weight loss, they have in recent years been found to impact our biology in ways that may have adverse effects on our metabolism.  Rather than helping in a quest for weight loss, is it possible that sweeteners could actually cause weight gain and metabolic disease?

A recent systematic review and meta-analysis was recently published in the Canadian Medical Association Journal, which collected the currently available evidence to try to answer this question and received worldwide attention in doing so.  They included 37 trials (including 7 randomized controlled trials and 30 cohort studies), looking at a total of over 400,000 individuals (about 1,000 of whom were in the randomized studies).

In their analysis of the randomized controlled trials, over a median follow up of 6 months, they found no significant effect on body mass index (BMI) or measures of body composition.  So, use of sweeteners did not result in weight loss, but there was no weight gain seen either.

In the cohort studies, over a median follow up of 10 years, they found an increase in weight, BMI, and waist circumference, and a higher incidence of obesity, metabolic syndrome, type 2 diabetes, high blood pressure, stroke, and cardiovascular events.

So overall, none of the evidence assessed showed a benefit to weight, and the observational data suggested adverse effects of sweeteners on weight and health - none of which is good news.  And why is there a difference in conclusions between the randomized trials versus the observational (cohort) data?

Well, it's possible that the randomized trials were not long enough or big enough to show a negative impact on health, and that if they had been longer trials, perhaps results would have been different.

On the other hand, observational (cohort) data does not give us as trustworthy of an answer to any research question, because the results can be muddied by other factors. One concern is that these data may be confounded by 'reverse causation' - meaning that people with obesity, or those more prone to develop obesity (eg family history of obesity) are more likely to use sweeteners to help manage their weight (rather than the sweeteners being the cause of weight gain).

Either way, there is research to suggest biological mechanisms by which sweeteners could have an adverse impact on our metabolic health, particularly in relation to changes they induce in our gut bacteria, as well as our neurobiological response to these chemicals.  Further research is clearly needed to better understand their effect on our health.

Remember also that there is no doubt that excess sugar consumption is associated with weight gain and all of the above metabolic complications - so swapping sugar back in is not the answer either.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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Children's Fitness Falls In Summer

You'd think that summertime would be a time of peak physical fitness for kids, right?  The weather is great, the days are long, school is out, and there is nothing but time for just being a kid... running, jumping, playing all day long.

Think again.

A study in the UK, which was presented recently at the Congress of the European College of Sport Science, tracked the fitness of over 400 children for just over a year.  They found that at the start of the school year in September, kids were not able to run as far as they could at the end of the prior school term in June.   They also found that body mass index (BMI) climbed between June and September (though BMI percentile would be the more appropriate measure).  The decrease in fitness was particularly evident in kids from areas of lower socioeconomic status.

These findings suggest that kids may be more often spending their summer holidays being inactive, perhaps in front of the TV or video games rather than being active in the great outdoors.  Active child care activities during the summer (eg summer camps) can be costly, so kids from less affluent homes may have less access to organized activities.

If you're having trouble keeping your young ones active this summer, here are some suggestions:

• Limit screen time.  Kids will find other things to do that are likely more active.
• Check out your local community facilities, parks and pools to see what is on offer.  
• Enjoy the warm weather and bright evenings with a family walk or bike ride! 
• Consider signing your kids up for a race (eg family fun run, or even a kids' triathlon!) and get them engaged to train for it.  

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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Testing Blood Sugar - Is There A Point?

In the management of people with diabetes, we routinely equip patients with glucose meters and ask them to check sugars at home.  While the importance and utility of checking sugars at home for people using insulin is clear, there is much debate about whether this is useful for people with type 2 diabetes who are not on insulin.  A recent study, which got a lot of media hype, tackled this question.

The study, published in JAMA Internal Medicine, randomized 450 people with type 2 diabetes and not using insulin, to either a) no home glucose montoring; b) checking sugars once daily; or c) checking sugars once daily plus automated educational/motivational messages delivered to the patient from the meter.

The researchers found that there was no difference in diabetes control (A1C) nor health related quality of life after 1 year, and concluded that glucose monitoring in people with non-insulin-treated type 2 diabetes should not be routine.

I have some major beefs with this conclusion:

1.   Testing once a day does not tell a person very much about their blood sugar.   In order for home testing to be useful, I advise 'paired meal testing': checking before a meal, and checking again 2 hours later.  This can be very helpful to see how certain types of food affect your blood sugar, and can be help to eat mindfully and manage portion control.  I don't necessarily advise doing this every day: checking each of breakfast, lunch, and dinner once per week can be enough.  However, depending on what kind of medication a person is taking, I may recommend more often.  Also, if diabetes control is not great, then checks (in my opinion) should be done more frequently so that we can figure out how to bring down the sugars effectively and safely.

2.  As the authors note, the study was not powered to determine if there are benefits to checking sugars around the time of medication or dose changes.  It is very difficult for a doctor to know what the next best medication may be without knowing the pattern of blood sugars through the day.  Knowing the pattern of blood sugars is extremely important when new medications are added onto sulfonylureas and insulin in particular, because these medications can cause low blood sugar.  For example, if sugars are highest in the morning and lower later in the day, there is a risk of causing low sugars if a treatment is added that brings down sugars in the morning (as sugars later in the day will go down too).

3.  Compliance with sugar checks in the study was poor by one year, declining gradually over the year, with only about 55% of people in the monitoring groups checking sugars each day by the 1 year mark.  Interestingly, the diabetes control (A1C) was better at 3, 6, and 9 months in the glucose monitoring groups, compared to those not monitoring - perhaps the lack of difference in A1C by 1 year was due to the poor compliance with glucose checks by that point in time.

4.  The study team did not engage with patients after their baseline visit - meaning patients were on their own to interpret their blood sugars without help from the study team.  Their family doctors received a copy of blood sugar results, but the study did not collect info on what was done with that data, and these clinicians had minimal interaction with the study team.  

Diabetes is a team sport - an important part of the benefit of checking blood sugars is to discuss these results with your health care team for help in optimizing control.  While the setup of this study was intended to be 'real world', I would submit that what patients perceived as their 'health care team' during the study (their usual doctors plus study investigators) were not working as a team and this may have limited the best possible use of home glucose monitoring.  And perhaps compliance with checking sugars in the study would have been better if that team was working together and more engaged with the patients, as is the ideal model of care.  We are blessed in Canada to be able to say that for most people in our country, the 'real world' does consist of free access to a team to help each individual with their diabetes care.

5.  For any patient on a sulfonylurea (and of course insulin), sugars must be checked before driving.   For a paper to conclude that glucose monitoring should not be routine (in a study where 36% of patients were on sulfonylurea!) is inappropriate.

Unfortunately, the media took hold of this study and has been shouting from the rooftops that people with non-insulin-requiring diabetes do not need to check their blood sugar.    I would be most saddened if patients get the message that they should stop testing their blood sugars, and would strongly advise people to continue to follow their doctor or diabetes educator's recommendations on how frequent of sugar checks is appropriate.

I hope this blog helps to provide some balance and perspective on what I feel is a study full of limitations.

Disclaimer: I have received speaking honoraria from makers of glucose meters.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2017

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