April 21st, 2015

What is the Proper Dosage of Jogging?

Proper Jogging TimeIntroduction:

There is no question that a sedentary lifestyle is a major risk factor for cardiovascular disease (CVD) and an early death. But a new study provides data to make it easy to conclude, that people who go to the opposite end of the spectrum and run too much suffer the same consequence. As usual, there is more to the story before “running” to a conclusion.

Background Data:

Regular exercise protects against the development of CVD and also favorably modifies other CVD risk factors including high blood pressure, blood lipid levels, insulin resistance, and obesity. Exercise is also important in the treatment and management of patients with CVD or increased risk including those who have hypertension, stable angina, a prior heart attack, peripheral vascular disease, heart failure or are recovering from a cardiovascular event.

Despite the benefits of exercise, throughout history there have been reports of people dying from running too much or too far. The most famous case is that of Pheidippides, a running courier who in 490 B.C. is believed to have run from Marathon to Athens, Greece, a distance of approximately 25 miles, to bring news of the Athenian victory over the Persians. Upon reaching the Athenian Agora, he exclaimed “Nike!” (“victory”), and then collapsed and died.

One of the most famous studies on the effect of exercise and jogging on heart health is the Copenhagen City Heart Study. One analysis of this study was performed in a random sample of 1,878 joggers who were followed for up to 35 years and compared with 16,827 non-joggers showed that the increase in survival among joggers was 6.2 years in men and 5.6 years in women. This particular analysis also indicated that jogging up to 2.5 hour per week at a slow or average pace and a frequency of ≤3 times per week was associated with the lowest mortality. Those who jogged >4 hours per week, at a fast pace, and >3 times per week appeared to lose many of the longevity benefits noted with less strenuous doses of jogging. These findings were not entirely unexpected by the researchers as some other studies had shown that excessive exercise was just as bad for the heart as too little.

New Data:

In an effort to better evaluate the ideal dosage of jogging to improve longevity, researchers looked at a different set of data from the Copenhagen City Heart Study that used 1,098 healthy joggers and 3,950 healthy non-joggers being followed up since 2001. The aim of this study was to investigate the association between jogging and long-term, all-cause mortality by focusing specifically on the effects of pace, quantity, and frequency of jogging.

The joggers were divided into light, moderate, and strenuous joggers. Light joggers had a slow or average pace, approximately 5 miles per hour, <2.5 hours of jogging per week with a frequency of ≤3 times per week. Moderate joggers had a slow or average pace, ≥2.5 hours of jogging per week with a frequency of ≤3 times per week or fast pace, ≤4 hours of jogging per week with a frequency of ≤3 times per week or slow or average pace with a frequency of >3 times per week or fast pace, <2.5 hours of jogging per week with a frequency of >3 times per week. Strenuous joggers had a fast pace of more than 7 miles per hour and either >4 hours of jogging per week or ≥2.5 hours of jogging per week with a frequency of >3 times per week.

Compared with sedentary non-joggers, 1 to 2.4 hours of jogging per week was associated with the lowest mortality (71% reduction in risk). The optimal frequency of jogging was 2 to 3 times per week (68% reduction in risk) or less than 1 time per week (71% reduction in risk). The optimal pace was slow (49% reduction in risk) or average (62% reduction in risk).

The highest reduction in risk for mortality was found in light joggers (78%) followed by moderate joggers (34%). The strenuous joggers actually showed a mortality rate that was not statistically different from that of the sedentary group.


As someone that is extremely active and believes in the value of regular exercise, this study on the surface seems to go against that practice. However, as usual in these types of studies, there is more to the story. What do we really know about the value of exercise in the promotion of health? Quite a lot actually and there is significant value with regular exercise, but excessive exercise may be quite harmful as this study suggest.

First, higher intensity and dosages of exercise is associated with many health benefits including improved cardiovascular and respiratory function, reduced body fat percentage and in particular reduced abdominal adiposity (belly fat), improved blood sugar control, and better cholesterol levels. Exercise intensity may also improve mood, sleep, and self-esteem in a dose-dependent manner. So, this study does not represent the end-all in terms of evaluating the effects of exercise on longevity.

Other studies that have looked at exercise have also reported this U-shaped curve showing that too much exercise had the same risk of early mortality as too little exercise. In terms of running, it was suggested that the limit of health benefits started to erode when people started running more than 35 miles per week or walking more than 46 miles per week.

Before commenting on the findings of this study, I have to admit that I am not a runner. I do, however, put in considerable amount of time on elliptical and stair climbing machines and push my heart rate at about 70-80% for 45 minutes or up to an hour at least three times per week. I do get on the treadmill occasionally and will run 1 or 2 miles at what would be considered an average to fast speed (6-7 mph). So, in the context of the researched reviewed above, am I am working out too hard? Absolutely, but I am not worried about it at all for several reasons. In fact, I am convinced I am doing really good things for my heart and body by pushing my exercise frequency, duration, and intensity.

Let me explain. It is thought that the detrimental effects of excessive exercise are due to the fact that exercise promotes inflammation and oxidative damage. Yep, the very things linked to hardening of the arteries (atherosclerosis). However, a little dosage of exercise stimulates the body to produce anti-inflammatory and antioxidant substance. That is a great thing, but at an excessive dosage exercise may lead to damage to the heart and blood vessels in a way that accelerates heart disease and hardening of the arteries. I am not worried about my reaching the level to be considered excessive exercise because of all of the things I do with my lifestyle, diet, and dietary supplements that fight against atherosclerosis. In essence, I flood my body with protective factors such as getting plenty of sleep; promotion of the relaxation response through meditation and prayer; eating heart health promoting foods like richly colored fruit and vegetables, nuts and seeds, cacao polyphenols, and beneficial oils like olive; and I take a big dosage of protective dietary supplements such as fish oils, Theracurmin, numerous flavonoid-rich extracts, and many others.

For more information on how to protect your heart and vascular system, please down my free book on Cholesterol and Heart Health. You may also what to view my webinar on An Honest Appraisal of Statins and Their Alternatives


Schnohr P, O’Keefe JH, Marott JL, Lange P, Jensen GB. Dose of jogging and long-term mortality: the Copenhagen City Heart Study. J Am Coll Cardiol. 2015 Feb 10;65(5):411-9.

Dr. Michael Murray

April 14th, 2015

New Study Shows Probiotics May Prevent ADHD and Autism Spectrum Disorders

Autism & ADHD Prevention in Children

There is a growing amount of medical research indicating that alterations in the type of bacteria that live in our gastrointestinal (GI) tract can influence brain function, mood and overall mental health. A new study from Finland is the first to show that probiotic supplementation early in life may be an effective way to reduce the rising tide of brain disorders in children, such as attention deficit hyperactivity disorder and autism spectrum disorders.

Background Data:

Gastrointestinal (GI) disturbances are very common in children with brain disorders such as attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders (ASD) including Asperger’s syndrome (AS). A number of mechanisms have been suggested linking these brain disorders as well as some of the common digestive disturbances these kids experience to alterations in the gut bacteria.

One novel theory is that lower levels of beneficial gut bacteria such as Lactobacillus and Bifidobacteria in children with ASD and ADD leads to an increase in toxin-producing bacteria such as Clostridium species. One study that supports this link that a gut microbial imbalance, such as the presence of toxin-producing Clostridium species, could contribute to ASD behavioral symptoms involved 11 children with ASD who were treated for 8 weeks with vancomycin. This antibiotic is often used in the treatment of chronic diarrhea due to Clostridium difficile. In this small study, scores for behavior and communication improved significantly during the treatment period; however, these gains only lasted while the children were given the antibiotic. This study raises the possibility that using probiotics, rather than antibiotics, may be helpful in at least some cases of ASD and, perhaps, ADHD as well.

In addition to the possibility that children with ASD and/or ADHD may be influenced by the absorption of gut-derived bacterial toxins, an altered gut flora also leads to increased gut permeability. Several studies have shown that the integrity of the intestinal lining is compromised in both ADHD and ASD. Increased gut permeability could lead to the absorption of microbial byproducts as well as partially digested food-derived compounds that may affect brain cell function directly or lead to immune responses that could also affect brain cells. Since probiotics can also improve the gut barrier, they may provide additional benefits in ADHD and ASD through this mechanism as well. Furthermore, since approximately 80% of the immune system resides in and around the intestinal lining, probiotics may also favorably affect the immune system to reduce the GI inflammation often observed in children with ADHD and ASD.

Lastly, a recent study in healthy women showed that supplementation with a mixture of probiotic bacteria had significant effects on brain regions that control central processing of emotion and sensation indicating that the probiotic bacteria themselves may be capable of exerting beneficial effects directly on brain function and mood.

New Data:

To test the hypothesis that probiotic supplementation may protect against the development of ADHD and AS, researchers in Finland looked closer at a study that was originally designed to test the effect of early supplementation with a probiotic in infancy on the later development of eczema. The mothers of 159 children were recruited in the and randomized in double-blind, placebo-controlled manner to receive 10 billion colony-forming units of Lactobacillus rhamnosus or placebo daily for 4 weeks before expected delivery. After delivery, the capsule contents were given either to the children, or continuously to the mothers, if breast-feeding, for 6 months.

To evaluate for a possible link between probiotic supplementation and ADHD or AS, 75 of these children were evaluated by an experienced child psychiatrist or neurologist not involved in the study or follow-up and the children were randomized and blinded so as not to produce any study bias. Results showed that ADHD or AS was diagnosed in 6/35 (17.1%) children in the placebo and none in the probiotic group (0/40). The probability value of this occurring was 0.008 indicating that it was not due to chance, but rather to a clear effect.

Because fecal samples were stored, the researchers were able to analyze the children for gut bacteria during their first six months of life. What the researchers found was that the numbers of Bifidobacterium species bacteria in feces during the first 6 months of life was lower in children with ADHD and AS compared to the healthy children.

The researchers concluded “Probiotic supplementation early in life may reduce the risk of neuropsychiatric disorder development later in childhood possible by mechanisms not limited to gut microbiota composition.”


When I read this study, my immediate response was WOW. Not because the results were unexpected, but rather my surprise that someone actually studied the possibility that probiotic supplementation may offer significant protection against the development of AS and ADHD.

What are the takeaways from this study? Alterations in gut bacteria and/or GI function/integrity may be a major factor in the development of childhood behavioral disorders. I strongly encourage all expecting mothers to supplement their diets with a high quality probiotic supplement, continue with that supplement while breastfeeding, and give their infants a probiotic supplement when they are no longer being breastfed.

My specific product recommendations are for women to use the Ultimate Probiotic Women’s Formula from Natural Factors at a dosage of one capsule per day for general support that will provide 12 billion live bacteria. For infants and children, I recommend the Ultimate Probiotic Children Formula from Natural Factors. For children 0-5 years old: 1/2 teaspoon, 1 to 3 times per day. For children 6-12 years old: 1 teaspoon, 1 to 3 times a day. Both of these formulas contain a good dosage of Lactobacillus rhamnosus along with compatible other probiotic bacteria.


Pärtty A, Kalliomäki M, Wacklin P, Salminen S, Isolauri E. A possible link between early probiotic intervention and the risk of neuropsychiatric disorders later in childhood: a randomized trial. Pediatr Res. 2015 Mar 11. doi: 10.1038/pr.2015.51.

Dr. Michael Murray

April 7th, 2015

Low Vitamin D Levels Linked to Depression


Depression is a major public health problem, especially in women. Recent statistics indicate that approximately 63% of American women and 35% of men will experience clinical depression at some point in their lifetime. While depression is clearly a multifactorial disorder, new research from Oregon State University shows that low blood levels of vitamin D are associated with clinically significant symptoms of depression in otherwise healthy individuals.

Background Data:

A number of population-based studies indicate that low levels of vitamin D may contribute to depression. Possible mechanisms include that there are receptor sites for vitamin D distributed in brain areas involved in the processing of emotions. Vitamin D also regulates the manufacture of key brain chemicals like serotonin that are involved in the regulation of mood. Vitamin D also dampens the inflammatory response in the brain looked at as a key influencer in influencing mood by activating the stress response.

Several studies have looked at the association between vitamin D sufficiency status and depression, but these studies were inconclusive. In addition, there have also been clinical trials where vitamin D supplementation was used to try to alleviate the depression in subjects with low vitamin D levels. These studies have also been inconclusive.

In addition to evaluating the role of vitamin D in depression, there is some evidence that it plays a central role in seasonal affective disorder (SAD) and seasonality (the milder spectrum of sensitivity of mood and behavior to seasonal changes). The so-called “winter blues.”

New Data:

To further evaluate the role of vitamin D in depression, female undergraduate students living in the Pacific Northwest during fall, winter, and spring academic terms completed the Center for Epidemiologic Studies Depression (CES-D) scale weekly for 4 weeks. The women also had their blood levels for vitamin D3 and C determined.

Lower vitamin D3 levels predicted clinically significant depressive symptoms. There was some evidence that lower levels of depressive symptoms in Fall participants (vs. Winter and Spring) were explained by their higher levels of vitamin D3.

These findings are consistent with other studies showing association between low levels of vitamin D and symptoms of depression. Noting that vitamin D supplementation is a low-cost, simple and low-risk intervention, the researchers recommended that the preventive value of D3 supplementation be tested.


This new study adds to the growing evidence on the importance of vitamin D3 in human nutrition. Most adults need to be supplementing with 2,000 to 5,000 IU of vitamin D3 each day, depending on their sun exposure.

In addition to vitamin D3, an insufficiency of the long chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fish oils has also been linked to depression. Studies have also reported that countries with high rates of fish oil consumption have low rates of depressive disorder. Because the brain is the richest source of fats in the human body and proper nerve cell function is critically dependent on proper cell membrane function, the benefits of omega-3 fatty acids are thought to be primarily due to improving cell membrane function.

Studies have shown that the fish oils impact the physical properties of cell membranes thereby influencing membrane fluidity; brain signal transmission; neurotransmitter synthesis and binding as well as the uptake of serotonin and other neurotransmitters. Bottom line is that fish oils rich in EPA+ DHA provides powerful nutritional support for brain health and a positive mood. In depression, the recommended dosage is 3,000 mg EPA+DHA daily.


Kerr DC, Zava DT, Piper WT, et al. Associations between vitamin D levels and depressive symptoms in healthy young adult women. Psychiatry Res. 2015 Mar 5. pii: S0165-1781(15)00108-0.

Dr. Michael Murray