f the fittest. Primitive man hadto forage and hunt for food from nature. Therefore, humans developed keen tastereceptors for fat-rich, caloric foods. Because the availability of food was uncertain, thosewho had stores of fat in their bodies, would be more able to survive the harsh conditionsof primitive life.
In modern times, we still have the same though weakened taste receptors ofprimitive man. Thus, we still have the affinity for sugar because sugar was hard to comeby in primitive times-all sugar had to be supplemented by plants and fruits. But mostly,today, the affinity for fat has been responsible for a multi-million dollar diet foodindustry. Recently, Procter&Gambol has synthesized a fat which does not behave likeother fats. It is a synthetic substance, because it is not found in nature, called Olestra(Olean commercially).Other attempts have been made for the perfect fat substitute, from using applesauce in cake batters to prune juice. But never has there been a successful fat-freesubstitute which is actually a fat.
This synthesized substance, Olestra, is touted to be theultimate fat. It has the same richness that characterizes fat, and which satisfies our tonguereceptors. Olestra is also heat-resistant, which means that traditionally fatteningfast-foods and junk foods, can be prepared with fat-free oil. The development of Olestra came serendipitously when scientists started toresearch different fat forms for infants in 1959.
Infants need high fat diets to begin with,but it was apparent that premature infants had a hard time digesting certain fats soresearch was done in finding a fat which could be more easily digested.Scientists first experimented with the traditional ester model of a fat. Acombination of an alcohol, sorbitol, and fatty acids.
They tried attaching only 1 fatty acid,and found that the result was well digested. When they tried 2 F.A.s the resultingmolecule was even better digested and best digested when 3 F.A.s were used.
But whenthey tried attaching 4-6 F.A.s, the structures digestibility progressively got worse, until 6fatty acids were completely indigestible.
This sorbitol/acid ester interested scientists, andthey decided to take their research further, and toward a different direction, that of fatindigestibility. Sorbitol was an expensive commercial food ingredient, so sucrosepolyesters were used instead. In accordance with the triglyceride model, a polyester ofsucrose (C12H22O11) rings bound by alcohol groups with 6-8 fatty acid side chains.
Thisis known as sucrose polyester.The body absorbs triglycerides, but not Olestra though they are both largemolecules. Other triglycerides are cut up by enzymes called lipase in our intestines by thelock and key mechanism. But in the case of Olestra, there is no space between thecramped fatty acid molecules, and so the spaces between the fatty acid molecules areconcealed, hidden, rendering lipase useless. This is why Olestra can go through thegastrointestinal tract without being digested or absorbed. Along with the innovations of this discovery, come the faults of the originalOlestra structure. In preliminary findings, Olestra caused vitamin depletion. VitaminsA,D,E, and K are fat soluble.
They attach to fat. So when Olestra comes along, thevitamins would go through the GI tract too. Procter&Gambol corrected this problem byadding vitamins to foods containing Olestra. This way, the Olestra molecules need tobind to vitamins was gone, and no additional absorption of vitamins occurred.Carotenoids such as carrots, cantaloupe, and dark-green, leafy vegetables had asimilar problem. Carotenoids aid in preventing many types of cancers but some are fatsoluble.
P&G did not correct this problem because carotenoids and Olestra were notnormally mixed by most people. Ex. broccoli and potato chips, crackers and cantaloupe.Depletion only occurs when these two are consumed at the same time.The politics involved in marketing Olestra was rigorous. In 1971, P&G appliedfor its first patent for Olestra. The FDA usually takes 1/2-6 years to review suchproposals.
Tests still showed that Olestra still caused minor GI problems such asflatulence and diarrhea, but not clinical diarrhea, which is fatal. These problems werebothersome, but not dangerous. Tests had to be conducted and this was difficult becauseOlestra is a macro-molecule-it can take up as much as 1/3 the weight of the food it isbeing used in. It is not simply a food additive such as MSG. So toxicology tests onanimals could only be accurate if the usual testing dose of 100 times the human servingwas used. But that amount