Charcoal broiling

Drug/Food interactions Theophylline elimination is increased (half-life shortened) by a low carbohydrate, high protein diet, and charcoal broiled beef (due to a high polycyclic carbon content). Conversely, elimination is decreased (prolonged half-life) by a high carbohydrate low protein diet. Food may alter the bioavailability and absorption pattern of certain sustained-release preparations. Some sustained-release preparations may be subject to rapid release of their contents when taken with food, resulting in toxicity. It appears that consistent administration in the fasting state allows predictability of effects. 

CYP1A2 is known to play a significant role in the metabolism of aromatic amines, estradiol, and other drugs. Furthermore, it is known that CYP1A2 is induced by cigarette smoke and charcoal-broiled meat. 

A 3 ounce charcoal broiled steak per day (from polynuclear aromatic hydrocarbons) 0.5... 

Substrates Inhibitors Inducers CYP1A2 Acetaminophen, caffeine, clozapine, imipramine, theophylline, propranolol Most fluoroquinolone antibiotics, fluvoxamine, cimetidine Tobacco smoking, charcoal-broiled foods, cruciferous vegetables, omeprazole... 

Smoking and charcoal-broiled food may decrease drug level Monitoring Parameters... 

A2 Acetaminophen, antipyrine, caffeine, clomipramine, phenacetin, tacrine, tamoxifen, theophylline, warfarin Smoking, charcoal-broiled foods, cruciferous vegetables, omeprazole Galangin, furafylline, fluvoxamine... 

Environmental chemicals and pollutants are also capable of inducing P450 enzymes. As previously noted, exposure to benzo[a]pyrene and other polycyclic aromatic hydrocarbons, which are present in tobacco smoke, charcoal-broiled meat, and other organic pyrolysis products, is known to induce CYP1A enzymes and to alter the rates of drug metabolism. Other environmental chemicals known to induce specific P450s include the polychlorinated biphenyls (PCBs), which were once used widely in industry as insulating materials and plasticizers, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin, TCDD), a trace byproduct of the chemical synthesis of the defoliant 2,4,5-T (see Chapter 56). 

Diet. Diet is shown to affect the absorption, metabolism, and response to many drugs.12,30 Animal and human studies indicated that the total caloric input as well as the percentage of calories obtained from different sources (carbohydrates, proteins, and fats) influence drug pharmacokinetics.17,26 Specific dietary constituents such as cruciferous vegetables and charcoal-broiled beef can also alter drug metabolism.17... 

In humans it has been demonstrated that increasing the ratio of protein to carbohydrate in the diet stimulates oxidation of antipyrine and theophylline, while changing the ratio of fat to carbohydrate had no effect. In related studies, humans fed charcoal-broiled beef (food high in polycyclic hydrocarbon content) for several days had significantly enhanced activities of CYPs 1A1 and 1A2, resulting in enhanced metabolism of phenacetin, theophylline, and antipyrine. Studies of this nature indicate that there is significant interindividual variability in these observed responses. 

The significance of polycyclic aromatic hydrocarbons (PCH) formed in charcoal-broiled beef has been publicized with respect to the ability of these substances to alter the fate of drugs in the... 

Pantuck, E.J., et al. Effect of charcoal-broiled beef on phen-acetin metabolism in man. Clin Pharmacol Therap, 1979 25 88-95... 

Table III. Dimethylhydrazine-induced tumors in rats fed lyophilized charcoal broiled beef, raw beef or soybean protein...

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