January 20, 2014
251 Nutrient Co-Factors [20 January 2014]
Last week I explained how the unique features of the dose-response relationship for nutrients can skew the results of nutrient intake studies towards showing no benefit. Another reason why nutrient studies often find little or no benefit is that adequate levels of cofactors are rarely ensured. Unlike drugs, nutrients work better together, and often don’t work at all without certain others. To accurately test the effect of a single nutrient on a particular process (eg bone-building), all the other nutrients required for that process must be adequately available. For example, to test the effect of calcium supplementation, all the other nutrients required for bone building must be available in adequate amounts: vitamin D, vitamin K2, magnesium, protein, and certain B vitamins. Without ensuring adequate levels of these co-factors, the study results will be meaningless and misleading.
Most nutrient studies are designed following the drug model which attempts to eliminate the effect of all other variables. But instead of eliminating the effect of cofactors by ensuring adequate levels, they are too often simply ignored. The results may be accurate for what is actually being tested – e.g. that calcium supplementation alone does not significantly increase bone formation, but to conclude that calcium is worthless would be erroneous. Instead, further studies are required to determine the optimum levels of each of the other co-factors.
The failure to consider cofactors, along with the location on the dose-response curve discussed last week, is likely responsible for the “equivocal and sometimes contradictory” vitamin D trials referred to in the Editorial “Enough is Enough: Stop Wasting Money on Vitamin and Mineral Supplements” (J Annals Int. Med, 17 Dec 2013). In one sense I agree with the authors of this editorial when they state “…further large prevention trials [of vitamins] are no longer justified.” Conducting more poorly-designed nutrient trials that are incapable of testing what they purport to be testing would not only be a waste of time and money but their erroneous conclusions may dissuade many from actions that might improve their health.
Source: Robert Heaney – Some Rules for Studies Evaluating Nutrient Effects
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
January 13, 2014
250 The Nutrient Dose-Response Curve [13 January 2013]
Last week I discussed a medical journal editorial which claimed that supplements don’t work and are just a waste of money. I ended by introducing the nutrient paradox – how it can be that nutrients, by definition essential for life, frequently show little benefit in supplement studies. This week I will examine some of the reasons for this paradox.
Robert P. Heaney, MD, a world-renowned endocrinologist specializing in bone, calcium & vitamin D physiology, published an article in June 2013 titled “Some Rules for Studies Evaluating Nutrient Effects” which explores some reasons for this paradox.
Heaney also explains that the middle section of the curve where increasing dose increases benefits is generally much narrower for nutrients than for drugs, meaning there is a smaller range of intake that will show a particular effect. Nutrient studies will not detect any benefit outside of this narrow range which is approximately 1 order of magnitude (10x difference from the lowest to highest) for nutrients, compared to 2 or even 3 orders of magnitude (100x to 1000x) for drugs.
And because the curve is not linear (a straight line), pooling data from studies with different doses, different participant base levels, and/or different durations (length of study) will produce confusing, misleading results. The first study mentioned last week was one of these.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
January 6, 2014
249 Multivitamins – a Waste of Money? [6 Jan 2014]
Did you see any of the news headlines a few weeks ago like “Multivitamins a waste of money” or “Vitamin, mineral supplements offer no benefits”? These were newspaper reports of an editorial in the December 17 Annals of Internal Medicine which was commenting on three studies published in the same issue. The first was a review of 27 trials of single or paired vitamins which found no clear evidence of benefits on all-cause mortality, cardiovascular disease or cancer. The second was a large 12 year controlled study of elderly physicians which found no difference in cognitive decline between multivitamins and placebo. The third found no significant difference in recurring cardiovascular events (heart attack) with the use of a “high dose 28-component multivitamin”.
Based on these three studies, with vague reference to previous research with similar results, the editors concluded that effects – either beneficial or harmful – of multivitamins are too small to be detected with such small trials and, while conceding that there may be small benefits or harms in a small subgroup of the population, conclude that the “case is closed” and “…vitamins should not be used for chronic disease prevention.” The editors go beyond that, warning about certain harmful vitamins and even describing vitamin D studies (which have shown clear strong benefits in many different health areas) as equivocal and contradictory. What surprised me most though was their call to halt research: “…large prevention trials are no longer justified…” which scientists almost never do. Journalists (and their editors) with little science and no nutritional expertise then take these opinions (which is what an editorial really is) and run with them, concocting the misleading headlines, with accompanying articles, mentioned above.
This editorial raises so many important issues that it will require several columns for an adequate response. Next week I will discuss the nutrient paradox – how it can be that nutrients, by definition essential for life, frequently show little benefit in supplement studies. In later columns we’ll examine the three above-mentioned studies in more detail. Stay tuned! By the way I am still taking my vitamins.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
Based on these three studies, with vague reference to previous research with similar results, the editors concluded that effects – either beneficial or harmful – of multivitamins are too small to be detected with such small trials and, while conceding that there may be small benefits or harms in a small subgroup of the population, conclude that the “case is closed” and “…vitamins should not be used for chronic disease prevention.” The editors go beyond that, warning about certain harmful vitamins and even describing vitamin D studies (which have shown clear strong benefits in many different health areas) as equivocal and contradictory. What surprised me most though was their call to halt research: “…large prevention trials are no longer justified…” which scientists almost never do. Journalists (and their editors) with little science and no nutritional expertise then take these opinions (which is what an editorial really is) and run with them, concocting the misleading headlines, with accompanying articles, mentioned above.
This editorial raises so many important issues that it will require several columns for an adequate response. Next week I will discuss the nutrient paradox – how it can be that nutrients, by definition essential for life, frequently show little benefit in supplement studies. In later columns we’ll examine the three above-mentioned studies in more detail. Stay tuned! By the way I am still taking my vitamins.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
December 23, 2013
248 Phosphatidyl Serine [23 Dec 2013]
Last week I discussed the uses of phosphatidyl choline in cell membrane function; this week we’ll look at its molecular cousin, phosphatidyl serine (or PS for short) and its role in the brain. Like its choline counterpart, PS is a phospholipid found in the cell membrane, but in much smaller amounts. PS is particularly abundant in nerve cell membranes of the brain where it plays a role in inter-cell communication. Our bodies can create PS from phosphatidyl choline but can also obtain some directly from our food. PS occurs in meat, fish, and organ meats particularly brain, but by far the most abundant food source of PS is soy lecithin. As with phosphatidyl choline, our production of PS decreases as we age which may contribute to a decline in brain function.
Double-blind studies in the USA and Europe have shown that PS supplementation can reverse this trend. Specifically, taking PS has been found to improve short and long-term memory and concentration in people with mild to moderate cognitive dysfunction (it doesn’t help much with more severe dementia). PS has also been shown to improve mood, reduce depression and increase social interaction in older people. Phosphatidyl serine supplements, in dosages of 200mg per day, have been used successfully for children with ADHD. PS has also been used, in higher doses, by athletes to reduce exercise-induced stress and soreness.
Phosphatidyl Serine supplements used to be extracted from bovine brain but since the BSE (mad cow) epidemic manufacturers have switched to making it from either soy or sunflower lecithin. Most of the early studies were done with bovine PS – more recent studies with soy based PS have shown less consistent results.
Because phosphatidyl serine is found in every cell of the body, it is a very safe nutrient with only a few rare, mild side effects. The goal of supplementation is to bring the levels of PS in the cell membranes back to what it was when we were younger. Therapeutic effects are dose dependent. For prevention 100mg per day is recommended; to treat age-related mental impairment 200-300 may be needed. PS is commonly sold in 60 and 100mg strengths.
Sources:
Wikipedia Phosphatidylserine
Web MD PS Overview Information
Web MD PS Uses, Side Effects, Interactions
Soy PS study in Japan
Natural Factors monograph
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
Double-blind studies in the USA and Europe have shown that PS supplementation can reverse this trend. Specifically, taking PS has been found to improve short and long-term memory and concentration in people with mild to moderate cognitive dysfunction (it doesn’t help much with more severe dementia). PS has also been shown to improve mood, reduce depression and increase social interaction in older people. Phosphatidyl serine supplements, in dosages of 200mg per day, have been used successfully for children with ADHD. PS has also been used, in higher doses, by athletes to reduce exercise-induced stress and soreness.
Phosphatidyl Serine supplements used to be extracted from bovine brain but since the BSE (mad cow) epidemic manufacturers have switched to making it from either soy or sunflower lecithin. Most of the early studies were done with bovine PS – more recent studies with soy based PS have shown less consistent results.
Because phosphatidyl serine is found in every cell of the body, it is a very safe nutrient with only a few rare, mild side effects. The goal of supplementation is to bring the levels of PS in the cell membranes back to what it was when we were younger. Therapeutic effects are dose dependent. For prevention 100mg per day is recommended; to treat age-related mental impairment 200-300 may be needed. PS is commonly sold in 60 and 100mg strengths.
Sources:
Wikipedia Phosphatidylserine
Web MD PS Overview Information
Web MD PS Uses, Side Effects, Interactions
Soy PS study in Japan
Natural Factors monograph
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
December 16, 2013
247 Phosphatidyl Choline & Cell Membranes [16 December 2013]
Healthy bodies depend on healthy cells which in turn require healthy cell membranes. Cell membranes (CM) are the “skin” around each of the 100 trillion cells in our body that protect the cells, control movement of nutrients and waste products in and out of cells, and help give cells their shape. CMs are composed of proteins, cholesterol, and special fats called phospholipids, of which the most important is phosphatidyl choline (PC).
Phosphatidyl choline keeps cell membranes strong, supple and functioning properly. When we are born, 90% of the phospholipids in our CMs are PC; as we age this decreases until by 70 it can be as low as 10%. This affects all aspects of our health including our heart, blood vessels, liver, brain and other organs causing cardiovascular problems, memory loss, poor sleep, and much more. PC is also a precursor to acetylcholine, an important brain neurotransmitter.
Fortunately increasing our intake of this vital nutrient can reverse many of these conditions – turning the clock back as it were. Supplementing with PC can:
• normalize cholesterol and reduce triglycerides
• lower homocysteine levels, a known risk factor for heart disease
• improve health of arteries and veins and improve circulation
• reduce inflammation
• improve liver health and function
• improve digestion of fats
• improve brain health and function (memory)
• be used to treat Alzheimer’s, PMS, bipolar disorder and tardive dyskinesia
• boost the immune system
• increase production of glutathione, our body’s most important antioxidant
• make your skin look and feel healthier
• increase energy and endurance
Food sources of PC include egg yolks, liver, peanuts, sunflower seeds and soybeans. It is also available as a supplement in capsule form. PC is similar to, and is a component of, lecithin.
Sources:
Institute for Natural Healing newsletter 9 Dec 2013
Wikipedia "Phosphatidyl Choline"
WebMD "Phosphatidyl Choline"
Natural Factors (a manufacturer of PC) "Phosphatidyl Choline"
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
Phosphatidyl choline keeps cell membranes strong, supple and functioning properly. When we are born, 90% of the phospholipids in our CMs are PC; as we age this decreases until by 70 it can be as low as 10%. This affects all aspects of our health including our heart, blood vessels, liver, brain and other organs causing cardiovascular problems, memory loss, poor sleep, and much more. PC is also a precursor to acetylcholine, an important brain neurotransmitter.
Fortunately increasing our intake of this vital nutrient can reverse many of these conditions – turning the clock back as it were. Supplementing with PC can:
• normalize cholesterol and reduce triglycerides
• lower homocysteine levels, a known risk factor for heart disease
• improve health of arteries and veins and improve circulation
• reduce inflammation
• improve liver health and function
• improve digestion of fats
• improve brain health and function (memory)
• be used to treat Alzheimer’s, PMS, bipolar disorder and tardive dyskinesia
• boost the immune system
• increase production of glutathione, our body’s most important antioxidant
• make your skin look and feel healthier
• increase energy and endurance
Food sources of PC include egg yolks, liver, peanuts, sunflower seeds and soybeans. It is also available as a supplement in capsule form. PC is similar to, and is a component of, lecithin.
Sources:
Institute for Natural Healing newsletter 9 Dec 2013
Wikipedia "Phosphatidyl Choline"
WebMD "Phosphatidyl Choline"
Natural Factors (a manufacturer of PC) "Phosphatidyl Choline"
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
December 9, 2013
246 Fruit and Fruit Juice [9 Dec 2013]
Last week I wrote about the benefits of eating nuts. Today I want to warn you of the risk of eating too much fruit, including dried fruit, and especially fruit juice.
Fruit is included in the Canada Food Guide for a reason. It provides us with vitamins, minerals, antioxidants, and other plant based nutrients like flavonoids, resveratrol and polyphenols, which are essential for good health. The drawback is that it also contains a lot of sugar (and most of it is fructose, the worst sugar as previously discussed).
The Food Guide (which I understand is greatly simplified to improve understanding and compliance) unfortunately lumps fruit in with vegetables, giving a range of 8-10 total servings for adult males aged 35-50. It is assumed you will choose a variety from both as there is a big difference nutritionally between 10 bananas and 5 cups of broccoli!
I also disagree with the Guide’s inclusion of canned fruit and fruit juice. Canned fruit is peeled and cooked so is depleted of most of its nutrients, and has added sugar (or pear juice which is really no better). Fruit juice is just as bad and is not much better than soda pop. There are few nutrients and little fiber left in juice but it has all (or more) of the sugar. And it’s much easier to over-consume juice than whole fruit.
A recent study from Harvard (published in the August 2013 British Medical Journal) using data from the Nurses Health Study (1991-2009) – the same source as the nut study in last week’s article – found that certain whole fruits, especially blueberries, grapes and apples, reduced the risk of Type 2 Diabetes while fruit juice significantly increased the risk. Because of its high fructose content, fruit juice also increases your risk of gout, high blood pressure and, of course, obesity.
Dried fruit has most of the nutrients and fiber but also has all of the sugar of whole fruit. The problem, as with juice, is that it’s easy to overdo it. Eat no more of it than you would the whole fruit, and drink extra water to help with digestion.
The best way to eat fruit is fresh, whole and raw. Berries have the most nutrients and the least sugar. Other fruits with lower sugar are prunes, apricots and kiwifruit. The highest are mango, pears and watermelon. If you are diabetic or insulin-resistant be especially careful to limit these. See Dr. Mercola's fructose chart here.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
Fruit is included in the Canada Food Guide for a reason. It provides us with vitamins, minerals, antioxidants, and other plant based nutrients like flavonoids, resveratrol and polyphenols, which are essential for good health. The drawback is that it also contains a lot of sugar (and most of it is fructose, the worst sugar as previously discussed).
The Food Guide (which I understand is greatly simplified to improve understanding and compliance) unfortunately lumps fruit in with vegetables, giving a range of 8-10 total servings for adult males aged 35-50. It is assumed you will choose a variety from both as there is a big difference nutritionally between 10 bananas and 5 cups of broccoli!
I also disagree with the Guide’s inclusion of canned fruit and fruit juice. Canned fruit is peeled and cooked so is depleted of most of its nutrients, and has added sugar (or pear juice which is really no better). Fruit juice is just as bad and is not much better than soda pop. There are few nutrients and little fiber left in juice but it has all (or more) of the sugar. And it’s much easier to over-consume juice than whole fruit.
A recent study from Harvard (published in the August 2013 British Medical Journal) using data from the Nurses Health Study (1991-2009) – the same source as the nut study in last week’s article – found that certain whole fruits, especially blueberries, grapes and apples, reduced the risk of Type 2 Diabetes while fruit juice significantly increased the risk. Because of its high fructose content, fruit juice also increases your risk of gout, high blood pressure and, of course, obesity.
Dried fruit has most of the nutrients and fiber but also has all of the sugar of whole fruit. The problem, as with juice, is that it’s easy to overdo it. Eat no more of it than you would the whole fruit, and drink extra water to help with digestion.
The best way to eat fruit is fresh, whole and raw. Berries have the most nutrients and the least sugar. Other fruits with lower sugar are prunes, apricots and kiwifruit. The highest are mango, pears and watermelon. If you are diabetic or insulin-resistant be especially careful to limit these. See Dr. Mercola's fructose chart here.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
December 2, 2013
245 Enjoy Nuts and Live Longer [2 Dec 2013]
A recent study out of Harvard brings good news for nut lovers – just in time for the holidays. Published November 21, 2013, in the New England Journal of Medicine, the authors showed that those who ate a handful of nuts daily lived longer and healthier.
The data was taken from the Nurses’ Health Study (1980-2010) and the Health Professionals Follow-up Study (1986-2010) which followed 76,464 women and 42,498 men over 25 to 30 years making it the largest study of its kind. Total mortality and cause-specific mortality was correlated with nut consumption. They found that those who ate more nuts had:
• 11% reduction in cancer deaths (during the study period)
• 29% reduction in deaths from heart disease
• 20% reduction in deaths from any cause
Those who ate nuts more frequently generally had a healthier lifestyle – they were also leaner, less likely to smoke, and more likely to exercise, take multi-vitamins, and to eat more fruits and vegetables. Curiously they also drank more alcohol (beer and peanuts watching TV sports?). The study was designed to isolate the effect of nut consumption from these other factors. Both peanuts and tree nuts provided similar reductions in mortality.
The more frequently that nuts were consumed, the lower the risk of death. The reduction in mortality varied from 7% for once a week through to 20% for once a day. While this study does not prove cause and effect, it is (to quote the authors)
See my column #43 21 Dec 2009 for more on “nut-rition”.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
The data was taken from the Nurses’ Health Study (1980-2010) and the Health Professionals Follow-up Study (1986-2010) which followed 76,464 women and 42,498 men over 25 to 30 years making it the largest study of its kind. Total mortality and cause-specific mortality was correlated with nut consumption. They found that those who ate more nuts had:
• 11% reduction in cancer deaths (during the study period)
• 29% reduction in deaths from heart disease
• 20% reduction in deaths from any cause
Those who ate nuts more frequently generally had a healthier lifestyle – they were also leaner, less likely to smoke, and more likely to exercise, take multi-vitamins, and to eat more fruits and vegetables. Curiously they also drank more alcohol (beer and peanuts watching TV sports?). The study was designed to isolate the effect of nut consumption from these other factors. Both peanuts and tree nuts provided similar reductions in mortality.
The more frequently that nuts were consumed, the lower the risk of death. The reduction in mortality varied from 7% for once a week through to 20% for once a day. While this study does not prove cause and effect, it is (to quote the authors)
“consistent with a wealth of existing observational and clinical-trial data in supporting the health benefits of nut consumption for many chronic diseases. In addition, nutrients in nuts, such as unsaturated fatty acids, high-quality protein, fiber, vitamins (e.g., folate, niacin, and vitamin E), minerals (e.g., potassium, calcium, and magnesium), and phytochemicals (e.g., carotenoids, flavonoids, and phytosterols), may confer cardioprotective, anticarcinogenic, anti-inflammatory, and antioxidant properties.” [NEJM 21 Nov 2013].
See my column #43 21 Dec 2009 for more on “nut-rition”.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
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