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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Do Omega-3s Lower Blood Pressure in Young, Healthy Adults?

Posted August 14, 2018 by Dr. Steve Chaney

What Is The Omega-3 Index And Why Is It Important?

Author: Dr. Stephen Chaney

 

Do omega-3s lower blood pressure in healthy adults?

omega-3s lower blood pressure young adultsThe literature on the potential health benefits of omega-3s is very confusing. That’s because a lot of bad studies have been published. Many of them never determined the omega-3 status of their subjects prior to omega-3 supplementation. Others relied on dietary recalls of fish consumption, which can be inaccurate.

Fortunately, a much more accurate measure of omega-3 status has been developed and validated in recent years. It’s called the Omega-3 Index. Simply put, the Omega-3 Index is the percentage of EPA and DHA compared to 26 other fatty acids found in cellular membranes. Using modern technology, it can be determined from a single finger prick blood sample. It is a very accurate reflection of omega-3 intake relative to other fats in the diet over the past few months. More importantly, it is a measure of the omega-3 content of your cell membranes, which is a direct measure of your omega-3 nutritional status.

A recent extension of the Framingham Heart Study reported that participants with an Omega-3 Index >6.8% had a 39% lower risk of cardiovascular disease than those with an Omega-3 Index <4.2% (WS Harris et al, Journal of Clinical Lipidology, 12: 718-724, 2018 ). Although more work needs to be done, an Omega-3 Index of 4% or less is generally considered indicative of high cardiovascular risk, while 8% or better is considered indicative of low cardiovascular risk. For reference, the average American has an Omega-3 Index in the 4-5% range. In Japan, where fish consumption is much higher and cardiovascular risk much lower, the Omega-3 Index is in the 9-11% range.

Previous studies have suggested that omega-3 fatty acids lower blood pressure to a modest extent. Thus, it is not surprising that more recent studies have shown an inverse correlation between Omega-3 Index and blood pressure. However, those studies have been done with older populations, many of whom had already developed high blood pressure.

From a public health point of view, it is much more interesting to investigate whether it might be possible to prevent high blood pressure in older adults by optimizing omega-3 intake in a young, healthy population, most of whom had not yet developed high blood pressure. Unfortunately, there were no studies looking at that population. The current study was designed to fill that gap.

 

How Was The Study Done?

omega-3s lower blood pressure young healthy adultsThe current study (M.G. Filipovic et al, Journal of Hypertension, 36: 1548-1554, 2018 ) was based on data collected from 2036 healthy adults, aged 25-41, from Liechtenstein. They were participants in the GAPP (Genetic and Phenotypic Determinants of Blood Pressure) study. Participants were excluded from the study if they had been diagnosed with high blood pressure and were taking medication to lower their blood pressure. They were also excluded if they had heart disease, chronic kidney disease, other severe illnesses, obesity, sleep apnea, or daily use of non-steroidal anti-inflammatory medications.

Blood samples were collected at the time of their enrollment in the study and frozen for subsequent determination of Omega-3 Index. Blood pressure was also measured at their time of enrollment in two different ways. The first was a standard blood pressure measurement in a doctor’s office.

For the second measurement they were given a wearable blood pressure monitor that recorded their blood pressure over 24 hours every 15 minutes during the day and every 30 minutes while they were sleeping. This is considered more accurate than a resting blood pressure measurement in a doctor’s office because it records the variation in blood pressure, while you are sleeping, while you are exercising, and while you go about your everyday activities.

 

Do Omega-3s Lower Blood Pressure In Young, Healthy Adults?

omega-3s lower blood pressure young adults equipmentNone of the participants in the study had significantly elevated blood pressure. The mean systolic and diastolic office blood pressures were 120±13 and 78±9 respectively. The average Omega-3 Index in this population was 4.6%, which is similar to the average Omega-3 Index in the United States.

When they compared the group with the highest Omega-3 Index (average = 5.8%) with the group with the lowest Omega-3 Index (average = 4.6%):

  • The office measurement of systolic and diastolic blood pressure was decreased by 3.3% and 2.6% respectively
  • While those numbers appear small, the differences were highly significant.
  • The 24-hour blood pressure measurements showed a similar decrease.
  • Blood pressure measurements decreased linearly with increasing Omega-3 Index. [In studies of this kind, a linear dose-response is considered an internal validation of the differences observed between the group with the highest Omega-3 Index and the group with the lowest Omega-3 Index.]

The authors concluded: “A higher Omega-3 Index is associated with statistically significant, clinically relevant, lower systolic and diastolic blood pressure in normotensive, young and healthy individuals. Diets rich omega-3 fatty acids may be a strategy for primary prevention of hypertension.”

 

What Does This Mean For You?

omega-3s lower blood pressure young adults questionPerhaps I should first comment on the significance of the relatively small decrease in blood pressure observed in this study.

  • These were young adults, all of whom had normal or near normal blood pressure.
  • The difference in Omega-3 Index was rather small (5.8% to 4.6%). None of the participants in the study were at the 8% or above that is considered optimal.
  • Liechtenstein is a small country located between Switzerland and Spain. Fish consumption is low and omega-3 supplement consumption is rare.

Under these conditions, even a small, but statistically significant, decrease in blood pressure is remarkable.

We should think of this study as the start of the investigation of the relationship between omega-3 status and blood pressure. Its weakness is that it only shows an association between high Omega-3 Index and low blood pressure. It does not prove cause and effect.

Its strength is that it is consistent with many other studies showing omega-3 fatty acids lower blood pressure. Furthermore, it suggests that the effect of omega-3s on blood pressure may also be seen in young, healthy adults who have not yet developed high blood pressure.

Finally, the authors suggested that a diet rich in omega-3s might reduce the incidence of high blood pressure by slowing the age-related increase in blood pressure that most Americans experience. This idea is logical, but speculative at present.

However, the GAPP study is designed to provide the answer to that question. It is a long-term study with follow-up examinations scheduled every 3-5 years. It will be interesting to see whether the author’s prediction holds true, and a higher Omega-3 Index is associated with a slower increase in blood pressure as the participants age.

 

Why Is The Omega-3 Index Important?

 

The authors of this study said: “The Omega-3 Index is very robust to short-term intake of omega-3 fatty acids and reliably reflects an individual’s long-term omega-3 status and tissue omega-3 content. Therefore, the Omega-3 Index has the potential to become a cardiovascular risk factor as much as the HbA1c is for people with diabetes…” That is a bit of an overstatement. HbA1c is a measure of disease progression for diabetes because it is a direct measure of blood sugar control.

In contrast, Omega-3 Index is merely a risk factor for cardiovascular disease. However, if it is further validated by future studies, it is likely to be as important for predicting cardiovascular risk as are cholesterol levels and markers of inflammation.

However, to me the most important role of Omega-3 Index is in the design of future clinical studies. If anyone really wants to determine whether omega-3 supplementation reduces cardiovascular risk, high blood pressure, diabetes or any other health outcome they should:

  • Start with a population group with an Omega-3 Index in the deficient (4-5%) range.
  • Supplement with omega-3 fatty acids in a double blind, placebo-controlled manner.
  • Show that supplementation brought participants up to an optimal Omega-3 Index of 8% or greater.
  • Look at health outcomes such as heart attacks, cardiovascular deaths, hypertension, stroke, or depression.
  • Continue the study long enough for the beneficial effects of omega-3 supplementation to be measurable. For cardiovascular outcomes the American Heart Association has stated that at least two years are required to obtain meaningful results.

These are the kind of experiments that will be required to give definitive, reproducible results and resolve the confusion about the health effects of omega-3 fatty acids.

 

The Bottom Line

 

An accurate measure of omega-3 status has been developed and validated in recent years. It’s called the Omega-3 Index. Simply put, the Omega-3 Index is the percentage of EPA and DHA compared to 26 other fatty acids found in cellular membranes.

Although more work needs to be done, an Omega-3 Index of 4% or less is generally considered indicative of high cardiovascular risk while 8% or better is considered indicative of low cardiovascular risk.

Previous studies have shown an inverse correlation between Omega-3 Index and blood pressure. However, these studies have been done with older populations, many of whom had already developed high blood pressure.

From a public health point of view, it is much more interesting to investigate whether it might be possible to prevent high blood pressure in older adults by optimizing omega-3 intake in a young, healthy population, most of whom had not yet developed high blood pressure. Until now, there have been no studies looking at that population.

The study described in this article was designed to fill that gap. The participants in this study were ages 25-41, were healthy, and none of them had elevated blood pressure.

When the group with the highest Omega-3 Index (average = 5.8%) was compared with the group with the lowest Omega-3 Index (average = 4.6%):

  • Both systolic and diastolic blood pressure were decreased
  • Blood pressure measurements decreased linearly with increasing Omega-3 Index.

The authors concluded: “A higher Omega-3 Index is associated with statistically significant, clinically relevant, lower systolic and diastolic blood pressure in normotensive, young and healthy individuals. Diets rich omega-3 fatty acids may be a strategy for primary prevention of hypertension.”

Let me translate that last sentence into plain English for you. The authors were saying that optimizing omega-3 intake in young adults may slow the age-related increase in blood pressure and reduce the risk of them developing high blood pressure as they age. This may begin to answer the question “Do omega-3s lower blood pressure in young, healthy adults?”

Or even more simply put: Aging is inevitable. Becoming unhealthy is not.

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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