From holistic websites to nutritional seminars, messages bombarding consumers and the profession argue that “natural” vitamins are better than “synthetics” and often espouse the “more is better” line for orthomolecular or megavitamin therapy.
Skeptics counter this by insisting that “with minor exception, molecules made in the ‘factories’ of nature are identical to those made in the factories of chemical companies.” 1 They maintain that a good diet should supply all necessary nutrients.
The true story builds a much more complex picture. With respect to the argument in favor of food-based vitamins, even natural sources of vitamin A in unnatural quantities produce problems like metabolic osteopathy in cats, a species with particularly high susceptibility to vitamin A toxicity. 2 For precursors to vitamin A, the carotenoids, as many as nine factors influence their bioavailability when ingested in food. These variables include:
- Their type, diversity and quantity.
. - The host’s nutrient status, genetic makeup and digestive health.
. - The integrity of the plant substrate when carotenoids are ingested in food. 3 , 4
The carotenoid lycopene, which lowers prostate cancer risk, illustrates this last point. Cooking improves lycopene bioavailability because heating and homogenizing lycopene-rich tomatoes into paste disrupts the fibrous plant cell walls, releasing the lycopene for absorption. 5 Partnering carotenoids with certain fats maximizes their...
Copyright 2009 BowTie Inc.
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