Breast Milk and IQ

A recent study looked at the effect of breast-feeding during infancy on the IQ of children over six years of age.(1) Mothers in the study were not told to breast-feed. Rather they were encouraged to do so with educational programs. Thus, two study groups were created: one with children breast-fed and the other with children fed from a bottle. Children who were breast fed scored higher on verbal, performance, and full-scale IQ tests. This is currently the largest study of its kind.

So what is in bottled milk that is preventing cognitive development? The answer is nothing. Breast milk is probably an unique formulation of fatty acids that promote cognition in infants. Bottled milk does not have these fats. In fact, research has shown that the effects of breast milk on IQ are dependent on genes involved in fat metabolism. Fatty acids are components of cell membranes and mediate numerous chemical reactions in the body. Not surprisingly, they would support the healthy development of the brain.

Reference

1. Kramer MS, Aboud F, Mironova E, et al. Breastfeeding and child cognitive development: new evidence from a large randomized trial. Arch Gen Psychiatry. Arch Gen Psychiatry. 2008 May;65(5):578-84.

Coming Up On Monday…Fruits of the NCCAM

Agent Orange and Cancer

Agent orange was a herbicide used in the Vietnam War as a defoliate. It is a mixture of chemicals called chlorphenoxy acids. These acids stimulate plant growth. When exposed, the plant is forced to grow so quickly that the energy demands cannot be met, and the plant dies. In Vietnam, the chemical was stored in orange barrels, hence the name. All sorts of health concerns have been raised since its use. But the danger is not from the chlorphenoxy acids themselves. Rather, dioxins are a byproduct of the manufacturing process and these are the real concern. The most common effect of dioxin on man has been a form of acne called chloracne. The link between dioxin and cancer has been somewhat controversial until the International Agency for Research on Cancer classified dioxin as a Group 1 carcinogen. The studies on Vietnam veterans exposed to Agent Orange largely support this conclusion.

Operation Ranch Hand was a U.S. military operation in which Agent Orange was dumped on Vietnam between 1962 and 1971. A study showed that the incidence of prostate cancer was similar in Vietnam Air Force veterans who sprayed Agent Orange and those who did not.(1) A more recent study found a strong link between spraying Agent Orange and both diabetes and prostate cancer when the data were adjusted for the calendar period of service, time spent in southeast Asia, and duration of spraying()2) Finally, data are being presented at the Annual Meeting of the American Urological Society that show prostate cancer incidence is twice as high in Vietnam veterans exposed to Agent Orange compared to those that were not. Veterans exposed to Agent Orange were more likely to have an aggressive cancer and be diagnosed at an earlier age.

As the evidence continues to mount, the link between dioxins and cancer is strengthening. The consequences of this research will extend beyond Agent Orange and the Vietnam War. Dioxins from cvarious sources are present in the environment, and the implications to human health are still being worked out.

References

1. Pavuk M, Michalek JE, Ketchum NS. Prostate cancer in US Air Force veterans of the Vietnam war. J Expo Sci Environ Epidemiol. 2006 Mar;16(2):184-90.

2. Michalek JE, Pavuk M. Diabetes and cancer in veterans of operation ranch hand after adjustment for calendar period, days of spraying, and time spent in southeast Asia. J Occup Environ Med. 2008 Mar;50(3):330-40.

3. Chamie K, deVere White RW, Ellison LM: Agent Orange exposure, Vietnam War veterans and the risk of prostate cancer. J Urol, suppl., 2008; 179: 149,
abstract 421.

Coming Up On Friday…The Danger of Milk Formulas

Keep It Up

Sildenafil citrate, which has the brand name Viagra, was developed in the mid 1980s as a treatment for angina and hypertension. Early clinical trials showed that sildenafil failed to relieve angina, but many men reported improved erectile function. Given this unexpected finding, research switched to the use of sildenafil as a treatment for impotence. Now sales of sildenafil are approximately one billion per year and it is the most studied drug. Sildenafil is approved for the treatment of pulmonary hypertension as well as impotence. Tadalafil (Cialis) and vardenafil (Levitra) are structurally similar to sildenafil, and all three have a common mechanism of action.
Blood entering and filling the penis causes penile erection. This filling is controlled by nitric oxide. Nitric oxide is released during sexual stimulation and interacts with an enzyme to produce the molecule cyclic guanosine monophosphate (cGMP). Production of cGMP causes relaxation of penile arteries and smooth muscle that results in blood filling the penis. An enzyme called phosphodiesterase 5 breaks down cGMP. Sildenafil improves and prolongs erectile function by inhibiting phosphodiesterase 5 and elevating cGMP levels. Enhancement of cGMP signaling also relaxes pulmonary blood vessels to alleviate pulmonary hypertension. Another enzyme that breaks down cGMP in the eye, phosphodiesterase 6, is also inhibited by sildenafil and vardenafil. Inhibition of this enzyme is responsible for the changes in colour perception and other visual disturbances sometimes reported during treatment with these drugs.
Many men with erectile dysfunction also suffer from cardiovascular disease. However, treatment with a phosphodiesterase 5 inhibitor and an organic nitrate such as glycerol trinitrate (nitroglycerin) is contraindicated. Anti-anginal drugs cause relaxation of blood vessels by releasing nitroc oxide and producing cGMP. Sildenafil itself marginally reduces blood pressure. Combined with an organic nitrate, however, the dual effects of the drugs on cGMP may cause dangerous hypotension.

Coming Up On Wednesday…Agent Orange