Obesity may not be solely due to excess carbs or evolutionary drives, but influenced by food additives and vitamins altering metabolic set points.
Discerning between 'wanting' and 'liking' of food, driven by dopamine and opioids, can impact behaviors like addiction and dietary preferences.
Mismatch in sweetness and calories affects satiety and metabolism, emphasizing the importance of food's sensory information for proper digestion.
Deep dives
Obesity Theories: Carbohydrate Insulin Model vs. Hungry Ape Theory
Westerners' weight gain has been attributed to two main theories: the Carbohydrate Insulin Model suggests excessive carb consumption drives obesity, while the Hungry Ape Theory points to an evolutionary drive to store fat. Studies like Kevin Hall's and the Diet Fits research challenge the Carbohydrate Insulin Model, revealing minimal metabolic differences based on dietary composition.
Pleasure Science: Dopamine's Role in Cravings and Enjoyment
Research on pleasure and dopamine shows the distinction between 'wanting' and 'liking'. Kent Berridge's experiments revealing that the desire for food can be disconnected from pleasure, illustrated by reactions in drug addicts. Dopamine drives wanting, while opioids contribute to liking, impacting behaviors like addiction and food preferences.
Matching Sweetness and Calories: Implications for Satiety
Dana Small's study on sweetness and calories shows a mismatch can affect satiety and metabolism. When sweetness and caloric content align, the brain responds effectively to process food. Adolescents' increased sweet preferences can lead to pre-diabetic conditions, highlighting the importance of food's sensory information for proper digestion.
Uncertainty and Reward Prediction Error in Food Consumption
Uncertainty in food's taste and nutritional content can create reward prediction errors in the brain, affecting perceptions of taste versus energy intake. The brain's meticulous tracking of food intake and expectations can be disrupted by mismatches in sweetness and calories, leading to metabolic challenges and potential health implications.
The Power of Uncertainty in Motivating Behavior
Uncertainty in cues has been found to increase motivation significantly based on research with rodents using illuminated levers. The notion that certainty in cues leads to predictability in behavior was challenged as rats became obsessed with the lever when outcomes were uncertain. This heightened motivation stemmed from an evolved response to uncertainty in nature, where a lack of clarity could signal danger, emphasizing the intrinsic link between uncertainty and motivation.
Role of B Vitamins in Weight Gain and Food Engineering
B vitamins play a crucial role in energy metabolism, enabling the body to convert food into weight-gaining capabilities. The fortification of flour with vitamins, particularly B vitamins, has been a common practice, contributing to weight gain in populations. The historical context of vitamin fortification in flour sheds light on its unintended consequences, underscoring how such modifications in food composition have impacted weight gain trends in society. The addition of energy metabolizing vitamins has potentially altered metabolic set points, making weight gain more likely and easier to achieve in modern dietary contexts.
There are two dominant theories as to why Westerners have gotten increasingly obese in the last fifty years. One is that we're eating too many carbs and carbs make us fat. Another is that our primitive appetite — which is wired to gorge on calorically dense foods as a survival mechanism — is misaligned with a modern landscape in which food is available in an overabundance.
My guest today says that there's too much evidence which contradicts these theories for them to completely explain the problem of weight gain, and forwards a different and quite surprising theory as to what may be going on instead. His name is Mark Schatzker and he's the author of The End of Craving: Recovering the Lost Wisdom of Eating Well. In order to arrive at Mark's theory on the rise in obesity, we first unpack several pieces of the puzzle, each fascinating in its own right. We discuss how the body, rather than having a natural propensity to gain weight, actually typically wants to stay at a healthy set point, the difference between wanting and liking and how obese people crave food more but enjoy it less, and why it is that humans take pleasure in eating. We then get to how food additives, like artificial sweeteners, and, strangely enough, even certain vitamins, may be shifting the body's set point, increasing people's craving for food, and triggering weight gain. We end our conversation with Mark's counterintuitive call to fight obesity by thoroughly enjoying truly delicious food.
