The Deadly CARET Study Explained
By: Lynne August MD
The Beta-Carotene and Retinol Efficacy Trial (CARET) was a randomized, double-blind, placebo-controlled trial to determine if a daily combination of 30 mg of beta-carotene and 25,000 IU of retinyl palmitate in 18,314 persons at high risk for lung cancer was safe and decreased the incidence of lung cancer. The Trial was terminated 21 months ahead of schedule for definitive evidence of no benefit and substantial evidence of an increase in the incidence of lung cancer and mortality from all causes. Two other findings were also unexplained: an increase in cardiovascular mortality and higher serum cholesterol and triglycerides in treated subjects compared to controls. Here we propose an explanation from Revici’s perspective.
Eur J Clin Nutr. 2005 Oct;59(10):1173-80[http://www.nature.com/ejcn/journal/v59/n10/full/1602229a.html?foxtrotcallback=true]
A dynamic interplay between anabolic and catabolic lipids defines a healthy metabolism, a swelling then receding tide. Disease manifests when the balance between these processes is lost. If prevalent, anabolism results in the likes of plaque, obesity and osteoarthritis whereas chronic inflammation, weight loss and rheumatoid arthritis are consequent of a catabolic off-balance. Both vitamin A and beta-carotene are catabolic lipids. Vitamin A and beta-carotene would have exacerbated the off-balance in subjects who already had a catabolic off-balance. The elevations in cholesterol and triglycerides were responses to the increase in catabolic fatty acid activity. Both cholesterol and triglycerides are anti-fatty acids. They bind fatty acids, arresting their inflammatory activity. The anti-fatty acid rally might have been protective in some subjects but certainly insufficient in those whose catabolic off-balance initiated cancer and CV events.
Fat-soluble vitamins A, D, E and K and adrenal and sex hormones are the most commonly prescribed lipids in everyday practice. Doses many-fold concentrations in body tissues or food can favorably or unfavorably impact the lipid defense. A, D, and testosterone are catabolic lipids whereas E, K, estrogens and cortisone are anabolic lipids. While water soluble vitamins, amino acids, mineral chelates and salts and other supplements can alkalize or acidify tissues, as catabolic and anabolic agents respectively do, their ability to determine or correct an off-balance in the lipid defense is negligible compared to lipids. The Health Equations Blood Test Evaluation ‘quantifies’ catabolic and anabolic activity. The novel Catabolic and Anabolic Indices have been developed clinically over the last three decades by collating metrics from blood and urine monitoring with clinical data. The Index with the highest score indicates the off-balance warranting treatment.