Another topic on my (rather long) list of how Taubes either misunderstands or misrepresents lipid metabolism and storage involves his use of terms related to "lipogenesis" (e.g. fructose is the most lipogenic of carbs) to imply that it leads to fat accumulation.
In his defense, there are any number of scholarly articles and texts that use the term lipogenesis to describe the "genesis" of fat stores. However they do so in the context of discussions of adipose tissue and do not conflate de novo lipogenesis and fat storage. Adipogenesis may not be exactly appropriate either, as this term is most correctly attributed to the formation of new fat cells. But at least the "adipo" implies fat tissue, thus it might loosely apply to the genesis of adipose tissue (whether by proliferation or filling of existing cells) rather than the synthesis of lipids per se.
Where obesity is concerned, we're interested in what causes changes in adipose tissue mass: increases or decreases.
In the past few years, fructose has become the new "saturated fat", to where fructophobes will avoid even carrots! This is due in large part to Lustig's alarmism, but Taubes weaves this into his lectures as well. We are to equate fructose with alcohol because it is processed in the liver and consider it particularly fattening because fructose elicits the highest rate of DNL of any carbohydrate. But just as carbohydrate per se is not uniquely fattening, neither is fructose per se. It is the processed tasty vehicles either in liquid form and/or packing a caloric whollop that are. Can you say ice cream?!
But back to the vocabulary, I've posted before demonstrating that lipogenesis does not contribute much to adipogenesis. See: Nutrient Fates after Absorption and Excess carbs converted to fat? But lipogenesis -- the synthesis of larger lipid molecules from smaller molecules -- is not only an energy consuming process, it may also be thermogenic as I posted about here: Fat Futile Cycling from Carb Excess (or more lay-friendly).
Bottom line, it is misleading to equate lipogenesis with fat accumulation in adipose tissue.
Where obesity is concerned, we're interested in what causes changes in adipose tissue mass: increases or decreases.
In the past few years, fructose has become the new "saturated fat", to where fructophobes will avoid even carrots! This is due in large part to Lustig's alarmism, but Taubes weaves this into his lectures as well. We are to equate fructose with alcohol because it is processed in the liver and consider it particularly fattening because fructose elicits the highest rate of DNL of any carbohydrate. But just as carbohydrate per se is not uniquely fattening, neither is fructose per se. It is the processed tasty vehicles either in liquid form and/or packing a caloric whollop that are. Can you say ice cream?!
But back to the vocabulary, I've posted before demonstrating that lipogenesis does not contribute much to adipogenesis. See: Nutrient Fates after Absorption and Excess carbs converted to fat? But lipogenesis -- the synthesis of larger lipid molecules from smaller molecules -- is not only an energy consuming process, it may also be thermogenic as I posted about here: Fat Futile Cycling from Carb Excess (or more lay-friendly).
Bottom line, it is misleading to equate lipogenesis with fat accumulation in adipose tissue.
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