Supplementation with vitamin C, vitamin E, or beta carotene doesn't do much to prevent cancer

Antioxidant supplements do not help much! In fact there have been studies that indicate they might do more harm than good.


Vitamins C and E and Beta Carotene Supplementation and Cancer Risk: A Randomized Controlled Trial.

Observational studies suggest that a diet high in fruits and vegetables, both of which are rich with antioxidants, may prevent cancer development. However, findings from randomized trials of the association between antioxidant use and cancer risk have been mostly negative....

Conclusions Supplementation with vitamin C, vitamin E, or beta carotene offers no overall benefits in the primary prevention of total cancer incidence or cancer mortality.

Energy drinks will rot your teeth.....

Popular Energy Drinks Cause Tooth Erosion, Study Shows

I was thinking of this study today while watching the 6 nations rugby matches, the cameras often showing the players slurping down bright blue (!) Powerade. I've posted before about some of the dodgy science behind these energy drinks.




Art DeVany also had something good:

You are slightly insulin resistant after a work out because growth hormone is an antagonist of insulin. Hence, any glucose that makes it into your blood stream will not be well-controlled and you will have excessive blood glucose, with all the consequences that this entails. It will be a mild form of elevated blood glucose, but it will be there nonetheless and it is to be avoided. Sports and gainer drinks are sold on the theory that exercise drains glycogen from the muscles and you must refill those stores. Nonsense. You want to drain the glycogen from your muscles, which you do through the glycolytic exercises that are part of the Evolutionary Fitness workout. One reason (and it may be the primary reason) people become insulin resistant and diabetic is because they never drain their muscles of glycogen and other energy stores. Muscle is the most insulin sensitive tissue in the body and you must have lots of it and drain it so that it retains its sensitivity and ability to soak up glucose from the blood stream. Replentishing muscle glycogen rapidly requires the ingestion of glucose in large doses. Once you compensate for the drained glycogen by refilling the muscle you lose the insulin sensitivity which the exercise produced. Athletes who supercompensate through carbohydrate loading to increase the glycogen content of their muscles, diminish their insulin sensitivity. Those who do no exercise have lower insulin sensitivity than more active individuals.

It is the progressive loss of insulin sensitivity that initiates the aging cascade. Aging becomes accelerated with diminishing insulin sensitivity as abdominal obesity begins to develop and glucose-triggered advanced glycation end products begin to accumulate. One of the main purposes of exercise is to enhance insulin sensitivity. When you ingest the gainer and replentishment drinks or attempt the supercompensation practiced by some endurance athletes (which was one of the things that started the pasta craze during the Berlin Olympics, a practice that has now been abandoned by elite athletes) you lose the sensitivity that was the objective of the exercise. You may even be worse off if you work out and practice compensation than had you just taken a walk.

The popularity of sports drinks and gainer protein supplements has a shred of physiology behind it and billions of dollars of commercial interest. These drinks and supplements rest on a reasonable physiological principle that is blown out of proportion into a vast business that has adverse health consequences. They destroy your insulin sensitivity and diminish the beneficial effects of exercise on sensitivity and total insulin action. They are also a source of excess calories that allows your growing insulin resistence to result in abdominal obesity over time. Sensitivity was one of the main objectives of the exercise in the first place. So, you nullify what is perhaps the most important benefit of the exercise. You definitely do not need the elevated blood glucose that comes from the many post work out drinks and bars that are sold out there.

Paradoxically, ingesting simple carbohydrates after a work out will cause an increase in your blood triglycerides (fats). This is because the growth hormone released by the work out releases fatty acids into the blood stream in preparation for using them as a source of energy to rebuild the muscle's energy stores and to fuel the clearance of damaged muscle cells. When blood glucose become elevated after the sports or other drink or bar, the body switches from using fat to using glucose, insulin is released in response to this and the effectiveness of growth hormone is diminished. The free fatty acids remain in suspension until the insulin response is strong enough to cause the fats to reesterfy and move back into adipose tissues. In the competition between fatty acids and glucose for scarce disposal pathways, glucose wins and the fat is left behind in the bloodstream where it can then precipitate onto the lining or enter the epythelium, with the help of insulin.

Another reason not to consume sports drinks is that they keep your sweet tooth alive and well. Sports drinks taste very sweet to someone like myself who consumes glucose so rarely that when I find it in a drink or food I am aware of it and find that it tastes peculiar and unpalatable. Small amounts of sugar produce a cloying taste response in me when they are not even noticed by others. Let's face it, every mass produced drink or manufactured food item has to be sweet in order to sell to the bulk of people whose food contains sugar in some form. They wouldn't sell if they didn't appeal to mass tastes that have already been conditioned to expect salt and sugar and fat. And it is an evolved adaptation to find glucose pleasant tasting. The brain lives on glucose for its energy and tastes evolved during a time when glucose was scarce. Take an energy-hungry brain that had to be protected during a time when glucose was scarce and you get a human animal with a strong preference for sweet substances.

More support for CoQ10

I have had a previous post about co enzyme Q10. Here is a new study on this supplement, which again suggests some benefits....

Effects of acute and 14-day coenzyme Q10 supplementation on exercise performance in both trained and untrained individuals


Background

To determine whether acute (single dose) and/or chronic (14-days) supplementation of CoQ10 will improve anaerobic and/or aerobic exercise performance by increasing plasma and muscle CoQ10 concentrations within trained and untrained individuals.

Methods

Twenty-two aerobically trained and nineteen untrained male and female subjects (26.1+/-7.6 yrs, 172+/-8.7 cm, 73.5+/-17 kg, and 21.2+/-7.0%) were randomized to ingest in a double-blind manner either 100 mg of a dextrose placebo (CON) or a fast-melt CoQ10 supplement (CoQ10) twice a day for 14-days. On the first day of supplementation, subjects donated fasting blood samples and a muscle biopsy. Subjects were then given 200 mg of the placebo or the CoQ10 supplement. Sixty minutes following supplement ingestion, subjects completed an isokinetic knee extension endurance test, a 30-second wingate anaerobic capacity test, and a maximal cardiopulmonary graded exercise test interspersed with 30-minutes of recovery. Additional blood samples were taken immediately following each exercise test and a second muscle biopsy sample was taken following the final exercise test. Subjects consumed twice daily (morning and night), 100mg of either supplement for a period of 14-days, and then returned to the lab to complete the same battery of tests. Data was analyzed using repeated measures ANOVA with an alpha of 0.05.

Results

Plasma CoQ10 levels were significantly increased following 2 weeks of CoQ10 supplementation (p<0.001); while a trend for higher muscle CoQ10 levels was observed after acute CoQ10 ingestion (p=0.098). A trend for lower serum superoxide dismutase (SOD) was observed following acute supplementation with CoQ10 (p=0.06), whereas serum malondialdehyde (MDA) tended to be significantly higher (p<0.05). Following acute ingestion of CoQ10, plasma CoQ10 levels were significantly correlated to muscle CoQ10 levels; maximal oxygen consumption; and treadmill time to exhaustion. A trend for increased time to exhaustion was observed following 2 weeks of CoQ10 supplementation (p=0.06).

Conclusions

Acute supplementation with CoQ10 resulted in higher muscle CoQ10 concentration, lower serum SOD oxidative stress, and higher MDA levels during and following exercise. Chronic CoQ10 supplementation increased plasma CoQ10 concentrations and tended to increase time to exhaustion. Results indicate that acute and chronic supplementation of CoQ10 may affect acute and/or chronic responses to various types of exercise.

synthetic vitamins and carbs bad....fat good....

Here is just a quick couple of tit-bits for the weekend:


Serious Dangers of Synthetic & Unnatural Vitamins (pdf) - Phil Maffetone looks at the same issue that I have pointed to recently. I really like Dr Maffetone. While I do not always agree with him, especially with respect to exercise, I think he was ahead of his time on things like shoes (simple, cheap and flat) and diet (low carb, higher fat).

Animal foods linked with reduced risk of breast cancer, while starch found to be associated with enhanced risk - Dr Briffa highlights "a piece of research which supports the notion that animal foods, even those rich in saturated fat, are not the dietary spectres they are so often made out to be. In addition, and I do think this is very important, it again supports the notion that the oh-so-health starchy carbs we are generally encouraged to have are fill of may have serious negative consequences for our health."

CoQ10 - A supplement that works?

If you have read previous posts (for example "Post Workout drinks are a waste of money") you may have picked up the idea that I think supplements are - by and large - a waste of money. Desperate athletes try anything to improve their performance but their purchases are often driven more by marketing than by any scientific research. This is something pointed out in the Intermittent Fasting book Eat Stop Eat.

However that isn't to say that all supplements are useless. For example I keep hearing positive things about CoQ10. Here is another study on this:

Reducing exercise-induced muscular injury in kendo athletes with supplementation of coenzyme Q10.

Intensive physical exercise may cause muscular injury and increase oxidative stress. The purpose of this study was to examine the effect of an antioxidant, coenzyme Q10 (CoQ10), on muscular injury and oxidative stress during exercise training. Eighteen male students, all elite Japanese kendo athletes, were randomly assigned to either a CoQ10 group (n 10) or a placebo group (n 8) in a double-blind manner. Subjects in the CoQ10 group took 300 mg CoQ10 per d for 20 d, while subjects in the placebo group took the same dosage of a placebo. All subjects practised kendo 5.5 h per d for 6 d during the experimental period. Blood samples were taken 2 weeks before, during (1 d, 3 d, 5 d) and 1 week after the training. Serum creatine kinase (CK) activity and myoglobin (Mb) concentration significantly increased in both groups (at 3 d and 5 d). Serum CK (at 3 d), Mb (at 3 d) and lipid peroxide (at 3 d and 5 d) of the CoQ10 group were lower than those of the placebo group. The leucocyte counts in the placebo group significantly increased (at 3 d) and neutrophils significantly increased in both groups (at 3 d and 5 d). Serum scavenging activity against superoxide anion did not change in either group. These results indicate that CoQ10 supplementation reduced exercise-induced muscular injury in athletes.

More questions over the value of supplements....

A couple of new studies that again question the value of supplements:

Effect of Glucosamine Sulfate on Hip Osteoarthritis - glucosamine sulfate is widely used by patients to treat osteoarthritis, despite inconclusive evidence of any benefit.

The abstract is available here

Background: The effectiveness of glucosamine sulfate as a symptom and disease modifier for osteoarthritis is still under debate.

Objective: To assess whether glucosamine sulfate has an effect on the symptoms and structural progression of hip osteoarthritis during 2 years of treatment.

Design: Randomized, controlled trial.

Setting: Primary care in the Netherlands.

Patients: 222 patients with hip osteoarthritis who were recruited by their general practitioner. Patients were eligible if they met the American College of Rheumatology clinical criteria for hip osteoarthritis.

Intervention: 2 years of treatment with 1500 mg of oral glucosamine sulfate or placebo once daily.

Measurements: Primary outcome measures were Western Ontario and McMaster Universities (WOMAC) pain and function subscales over 24 months and joint space narrowing after 24 months. The main secondary outcome measures were WOMAC pain, function, and stiffness after 3, 12, and 24 months.

Results: At baseline, both groups were similar in demographic and clinical variables. Overall, WOMAC pain did not differ (mean difference [glucosamine sulfate minus placebo], –1.54 [95% CI, –5.43 to 2.36]), nor did WOMAC function (mean difference, –2.01 [CI, –5.38 to 1.36]). Joint space narrowing also did not differ after 24 months (mean difference, –0.029 [CI, –0.122 to 0.064]). Only 1 of the sensitivity analyses, based on extreme assumptions regarding missing assessments due to total hip replacement, provided results consistent with a glucosamine effect.

Limitations: Twenty patients had total hip replacement during the trial. Half of the patients had a Kellgren and Lawrence score of 1.

Conclusion: Glucosamine sulfate was no better than placebo in reducing symptoms and progression of hip osteoarthritis.


Then there is this one which looks at the Effect of carbohydrate-protein supplement timing on acute exercise-induced muscle damage

The full paper is available here


Purpose: To determine if timing of a supplement would have an effect on muscle damage, function and soreness.

Methods

Twenty-seven untrained men (21+/-3 yrs) were given a supplement before or after exercise. Subjects were randomly assigned to a pre exercise (n=9), received carbohydrate/protein drink before exercise and placebo after, a post exercise (n=9), received placebo before exercise and carbohydrate/protein drink after, or a control group (n=9), received placebo before and after exercise. Subjects performed 50 eccentric quadriceps contractions on an isokinetic dynamometer. Tests for creatine kinase (CK), maximal voluntary contraction (MVC) and muscle soreness were recorded before exercise and at six, 24, 48, 72, and 96h post exercise. Repeated measures ANOVA were used to analyze data.

Results

There were no group by time interactions however, CK significantly increased for all groups when compared to pre exercise (101+/-43U/L) reaching a peak at 48h (661+/-1178U/L). MVC was significantly reduced at 6h by 31.4+/-14.0%. Muscle soreness was also significantly increased from pre exercise peaking at 48h.

Conclusions

Eccentric exercise caused significant muscle damage, loss of strength, and soreness; however timing of ingestion of carbohydrate/protein supplement had no effect.


Again, you have to question what is really useful and what is just the latest subject of an advertising campaign....