Carnitine, fatty acids protect; hot tea may be troublesome

In the realm of cancer prevention, this week’s boon may be next week’s blacklisted substance. A trio of recently released studies offers up a new, chemoprotective spin on familiar compounds.

First, the supplement L-carnitine alone or in combination with other natural chemopreventive compounds could be used to prevent, slow, or reverse the occurrence of liver cancer, according to a study conducted at King Saud University in Saudi Arabia.

The researchers, led by Professor Mohamed M. Sayed-Ahmed, found in the carnitine-depleted rat model a progressive increase in liver enzyme activities as well as massive degenerative changes and evidence of preneoplastic lesions in liver tissues (World J Gastroenterol 15:1373-1380, 2009).

L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes compared to normal values as well as normal liver histology and no evidence of preneoplastic lesions in liver tissues, the authors stated.

The group will continue working with L-carnitine in the hopes of answering such questions as what is the molecular mechanisms whereby carnitine deficiency provokes hepatic carcinogenesis? and what is the relationship between hepatic cancer and its resistance to cancer chemotherapy?

Next, omega-3 fatty acids can protect against advanced prostate cancer, even in patients with a COX-2 variant, according to a study done at the University of California, San Francisco.

John S. Witte, PhD, a professor of epidemiology and biostatistics at UCSF, and colleagues performed a case-control analysis of 466 men diagnosed with aggressive prostate cancer compared to 478 healthy men (Clin Cancer Res online, March 24, 2009)

Men who consumed the highest amount of long chain omega-3 fatty acids had a 63% reduced risk of aggressive prostate cancer compared with men who had the lowest amount of omega-3s.

Men with high omega-3 intake had a substantially reduced risk, even if they carried the COX-2 variant, the authors also found Finally, drinking scalding tea (70°C or more) can increase the risk of oesophageal cancer, according to a study out of Iran’s Tehran University of Medical Sciences.

Reza Malekzadeh, MD, and coauthors studied tea drinking habits among 300 people diagnosed with oesophageal squamous cell carcinoma and a matched group of healthy controls.

Compared with drinking warm or lukewarm tea (65°C or less), drinking hot tea (65-69°C) was associated with twice the risk of oesophageal cancer.

Drinking very hot tea (70°C or more) was associated with an eight-fold increased risk (BMJ online, March 26, 2009). Dr. Malekzadeh’s group did not find an association between the amount of tea consumed and risk of cancer.