Can Resveratrol Improve Memory Performance In The Elderly ?

Written by Dr. Steve Chaney on . Posted in Health Current Events, Healthy Lifestyle, Supplements and Health

red wine benefitsWill Red Wine Make You Smarter?

Author: Dr. Stephen Chaney

It seems like every other day a new headline pops up telling us of yet another nutrient that might improve memory and slow cognitive decline. Perhaps it’s because we having a greying population. Lots of Americans are looking for that magic pill that will allow us to remember where we left the car keys.

This week the banner headlines were about resveratrol, a polyphenol from red wine. The headlines suggested that resveratrol could improve memory performance in healthy older adults. Are those headlines true, and what does that information mean for you?

What is Resveratrol?

Resveratrol is a member of a very large class of compounds called polyphenols that are found in red wine, green tea, and a variety of fresh fruits and vegetables. Polyphenols are very diverse structurally, but most of them are excellent antioxidants. They are one of the reasons that we are constantly being told to eat more fresh fruits and vegetables.

However, resvertrol and a few structurally similar polyphenols are unique in that they also bind to proteins called sirtuins which regulate metabolic processes related to the aging process. In fact, resveratrol garnered a lot of attention a few years ago when Dr. David Sinclair at Harvard Medical School published a study showing that obese mice given resveratrol escaped many of the metabolic consequences of obesity and actually lived longer than mice who were not given resveratrol.

In animal studies resveratrol appears to improve insulin sensitivity and mitochondrial function, lower cholesterol levels and blood pressure, and reduce inflammation and oxidative damage. Human studies have been limited to date, but suggest that resveratrol may impart many of these metabolic benefits to humans as well.

A recent study showed that resveratrol improved memory performance in grey mouse lemurs, a non-human primate species. However, no one had previously looked at whether resveratrol might improve memory in humans.

Can Resveratrol Improve Memory In Healthy Older Adults?

improve memoryIn this study (A. V. Witte et al, The Journal of Neuroscience, 34: 7862-7870, 2014) investigators recruited 46 older (average age 64), overweight (BMI 25-30), adults from Berlin, Germany. All of the subjects were healthy and none of them had any sign of cognitive impairment. For a six month period half of them were given 100 mg of resveratrol twice a day, and half of them were given a placebo (sunflower oil).

At the beginning of the test period they were given a memory test which measures how many of 15 listed words they could recall 30 minutes later. They also underwent a MRI scan that measured brain volume and functional connectivity of the hippocampus, a key region implicated in memory function. Finally, hemoglobin A1c, a measure of long term blood sugar control was measured.

Here are the results:

  • There was a significant effect of resveratrol on retention of words over 30 minutes compared to placebo. Memory improved significantly in the resveratrol group, while it declined slightly in the placebo group.
  • There was no effect of resveratrol on brain volume compared to the placebo (most interventions showing significant effects on brain volume required 2-3 years to demonstrate a significant effect).
  • Subjects in the resveratrol group showed significant increases in functional connectivity of the hippocampus to other brain regions involved learning and memory compared to the placebo group.
  • Subjects in the resveratrol group had lower hemoglobin A1c (better long term blood sugar control) compared to the placebo group.
  • When they statistically evaluated individual patients, the degree of improvement in the word memory test correlated with the increase in functional connectivity of the hippocampus and both of those measures correlated with decreased hemoglobin A1c.

What Does This Study Mean?

This study is promising in that it is well done and is consistent with previous animal studies. However, we need to keep in mind that this is the very first study of this kind. Similar to most first studies, it is small (only 46 subjects) and short in duration (6 months). It also only tested one dose of resveratrol (200 mg/day).

Now that this study has shown that resveratrol might improve memory in healthy older adults, it provides a strong rationale for more clinical studies to test this hypothesis. There is a need for larger, longer term studies in other population groups. Future studies should also evaluate different doses of resveratrol so that we know how much is needed to positively impact mental function.

Can resveratrol improve memory?

The Bottom Line:

  • A recent study suggests that resveratrol, a polyphenol from red wine, improves memory (measured by a word recall test) and functional connectivity of the hippocampus, a region of the brain involved in memory function.
  • This is the very first study of its kind. It was small (46 subjects) and short (6 months). However, it was well designed and consistent with previous animal results. Thus, it should be considered preliminary, but promising. More studies are clearly needed to test this hypothesis.
  • If the results of this study are substantiated, it will not necessary mean that other polyphenols will exert similar effects on memory. The action mechanism of resveratrol is different than most other polyphenols.
  • It also does not necessarily mean that red wine will make you smarter. The 100 glasses of red wine a day that you would need to drink to get the amount of resveratrol used in this study would probably kill more brain cells than the resveratrol could help.
  • Finally, as I said in a recent “Health Tips From the Professor” , there are no “magic bullets” when it comes to preventing cognitive decline. Your chances of reducing cognitive decline are best with a holistic approach that includes healthy diet, exercise, socialization, mental exercises, maintaining a healthy weight, B vitamins and omega-3 fatty acids. If this study is confirmed by future studies, you may be able to add resveratrol supplements to the list.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Does Protein Supplement Timing Matter?

Posted May 15, 2018 by Dr. Steve Chaney

How Do You Gain Muscle Mass & Lose Fat Mass?

Author: Dr. Stephen Chaney

 

protein supplement timingMost of what you read about protein supplements on the internet is wrong. That is because most published studies on protein supplements:

  • Are very small
  • Are not double blinded.
    • Both the subjects and the investigators knew who got the protein supplement.
  • Are done by individual companies with their product.
    • You have no idea which ingredients are in their product are responsible for the effects they report.
    • You have no idea how their product compares with other protein products.
    • There is no standardization with respect to the amount or type of protein or the addition of non-protein ingredients.

Because of these limitations there is a lot of misleading information on the benefits of protein supplements timing and maximal benefit. Let’s start by looking at why people use protein supplements. Let’s also look at what is generally accepted as true with respect to the best supplement timing.

There are 4 major reasons people consume protein supplements:

  • Enhance the muscle gain associated with resistance training: In this case, protein supplements are customarily consumed concurrently with the workout.
  • Preserve muscle and accelerate fat loss while on a weight loss diet: In this case, protein supplements are customarily consumed with meals or as meal replacements.
  • Provide a healthier protein source. In this case, protein supplements are customarily consumed with meals in place of meat protein.
  • Prevent muscle loss associated with aging or illness. There is no customary pattern associated with this use of protein supplements.

How good are the data supporting the customary timing of protein supplementation? The answer is: Not very good. The timing is based on a collection of weak studies which do not always agree with each other.

The current study  (J.L. Hudson et al, Nutrition Reviews, 76: 461-468, 2018 ) was designed to fill this void in our knowledge. It is a meta-analysis that compares all reasonably good studies that have looked at the effect of protein supplement timing on weight gain or loss, lean muscle mass gain, fat loss, and the ratio of lean muscle mass to fat mass.

How Was The Study Done?

The authors started by doing a literature search of all studies that met the following criteria:

  • The study was a randomized control trial with parallel design. This means that study contained a control group. It does not mean that the investigators or subjects were blinded with respect to which subjects used a protein supplement and which did not.
  • The subjects were engaged in resistance training.
  • The study lasted 6 weeks or longer.
  • Reliable methods were used to measure body composition (lean muscle mass and fat mass).
  • The subjects were healthy and at least 19 years old.
  • There was no restriction on the food the subjects consumed.

The authors started with 2074 published studies and ended up with 34 that met all their criteria. They then separated the studies into two groups – those in which the protein supplements were used with meals and those in which the protein supplements were used between meals.

Both groups were diverse.

  • Group 1 included subjects who consumed their protein supplement with their meal and those who consumed their protein supplement as a meal replacement.
  • Group 2 included subjects who consumed their protein supplement concurrent with exercise (usually immediately after exercise) and those who consumed their protein supplement at a fixed time of day not associated with exercise.

Does Protein Supplement Timing Matter?

 

protein supplement timing workoutsBecause the individual studies were very diverse in the way they were designed, the authors could not calculate a reliable estimate of how much lean muscle mass was increased or fat mass was decreased. Instead, they calculated the percentage of studies showing an increase in lean muscle mass or a decrease in fat mass.

When the authors compared protein supplements consumed with meals versus protein supplements consumed between meals:

  • Weight gain was observed in 56% of the studies of protein supplementation with meals compared to 72% of the studies of protein supplementation between meals. In other words, protein supplements consumed with meals were less likely to lead to weight gain than protein supplements consumed between meals.
  • An increase in lean muscle mass was observed in 94% of the studies of protein supplementation with meals compared to 90% of the studies of protein supplementation between meals. In other words, timing of protein supplementation did not matter with respect to increase in muscle mass.
  • A loss of fat mass was observed in 87% of the studies of protein supplementation with meals compared to 59% of the studies of protein supplementation between meals. In other words, protein supplements consumed with meals were more likely to lead to loss of fat mass.
  • An increase in the ratio of lean muscle mass to fat mass was observed in 100% of the studies of protein supplementation with meals compared to 87% of the studies of protein supplementation between meals. In short, protein supplements consumed with meals were slightly more likely to lead to an increase in the ratio of lean muscle mass to fat mass.

The following seem to suggest protein supplement timing matters:

The authors pointed out that their findings were consistent with previous studies showing that when protein supplements are consumed with a meal they displace some of the calories that otherwise would have been consumed. Simply put, people naturally compensate by eating less of other foods.

In contrast, the authors stated that previous studies have shown that when foods, especially liquid foods, are consumed as snacks (between meals), people are less likely to compensate by reducing the calories consumed in the next meal.

The others concluded: “Concurrently with resistance training, consuming protein supplements with meals, rather than between meals, may more effectively promote weight control and reduce fat mass without influencing improvements in lean [muscle] mass.”

What Are The Limitations Of The Study?

Meta-analyses such as this one, are only as good as the studies included in the meta-analysis. Unfortunately, most sports nutrition studies are very weak studies. Thus, this meta-analysis is a perfect example of the “Garbage In: Garbage Out (GI:GO)” phenomenon.

For example, let’s start by looking at what the term “protein supplement” meant.

  • Because the studies were done by individual companies with their product, the protein supplements in this meta-analysis:
    • Included whey, casein, soy, bovine colostrum, rice or combinations of protein sources.
    • Were isolates, concentrates, or hydrolysates.
    • Contained various additions like creatine, amino acids, and carbohydrate.
  • As I discuss in my book, Slaying the Food Myths, previous studies have shown that optimal protein and leucine levels are needed to maximize the increase in muscle mass and decrease in fat mass associated with resistance exercise. However, neither protein nor leucine levels were standardized in the protein supplements included in this meta-analysis.
  • Previous studies have shown that protein supplements that have little effect on blood sugar levels (have a low glycemic index) are more likely to curb appetite. However, glycemic index was not standardized for the protein supplements included in this meta-analysis.

protein supplement timing workout peopleIn short, the conclusions of this study might be true for some protein supplements, but not for others. We have no way of knowing.

We also need to consider the composition of the two groups.

  • Protein supplements used as meal replacements are more likely to decrease weight and fat mass than protein supplements consumed with meals. Yet, both were included in group 1.
  • Some studies suggest that protein supplements consumed concurrent with resistance exercise are more likely to increase muscle mass than protein supplements consumed another time of day. Yet, both are included in group 2. We also have no idea whether the meals with protein supplements in group 1 were consumed shortly after exercise or at an entirely different time of day.

This was the most glaring weakness of the study because it was completely avoidable. The authors could have grouped the studies into categories that made more sense.

In other words, there are multiple weaknesses that limit the predictive power of this study.

What Can We Learn From This Study?

Despite its many limitations, this study does remind us that protein supplements do have calories. This is of relatively little importance for people whose primary goal is to increase lean muscle mass.

However, most of us are using protein supplements to lose weight or to increase our lean mass to fat mass ratio. Simply put, we are either trying to lean out (shape up) or lose weight. And, we want to lose that weight primarily by getting rid of excess fat. For us, calories do matter. With that in mind:

  • If we are consuming a protein supplement immediately after exercise or between meals we probably should make a conscious effort to reduce our daily caloric intake elsewhere in our diet.
  • Alternatively, we could consume the protein supplement with a meal, but time the meal so it occurs shortly after exercise.

 

The Bottom Line:

 

A recent study looked at the optimal timing of protein supplements consumed by subjects who were engaged in resistance exercise. Specifically, the study compared protein supplements consumed with meals versus protein supplements consumed between meals on weight, lean muscle mass, fat mass, and the ratio of lean muscle mass to fat mass. The study reported:

  • Protein supplements consumed with meals were less likely to lead to weight gain than protein supplements consumed between meals.
  • Timing of protein supplementation did not matter with respect to increase in muscle mass.
  • Protein supplements consumed with meals were more likely to lead to loss of fat mass.
  • Protein supplements consumed with meals were slightly more likely to lead to an increase in the ratio of lean mass to fat mass.

The authors pointed out that their findings were consistent with previous studies showing that when a protein supplement was consumed with a meal it displaces some of the calories that would have been otherwise consumed. Simply put, people naturally compensate by eating less of other foods.

In contrast, the authors said that previous studies have shown that when foods, especially liquid foods, are consumed as snacks (between meals), people are less likely to compensate by reducing the calories consumed in the next meal.

As discussed in the article above, the study has major weaknesses. However, despite its many weaknesses, this study does remind us that protein supplements do have calories. This is of relatively little importance for people whose primary goal is to increase lean muscle mass.

However, for those of us who are using protein supplements to lose weight or to increase our lean mass to fat mass ratio, calories do matter.  With that in mind:

  • If we are consuming a protein supplement immediately after exercise or between meals we probably should make a conscious effort to reduce our daily caloric intake elsewhere in our diet.
  • Alternatively, we could consume the protein supplement with a meal, but time the meal so it occurs shortly after exercise.

For more details, read the article above:

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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