Over time, we may add health implications, including glycemic and insulinemic response in the context of diabetic conditions, but this write-up currently only addresses energy intake. Additionally, this model is targeted among countries where food is available in excess. Lastly, food recipes are not included in this model at the moment as recipes can vary due to different types and amounts of ingredients used with varying processes involved to obtain vastly different results and therefore leading to confounding results.
1. Important Terms
This would include foods that favor a negative energy intake, potentially below normalization of body fat.
This would include foods that favor a positive energy intake, potentially above normalization of body fat.
This would include foods that favor the normalization of body fat. Combining foods from either anorectic, obesogenic, and normalizing categories can lead to normalizing, depending on the end product and its compensatory response.
For example, leafy greens on their own may be anorectic but adding a sauce containing free sugars and emulsified fats that may be obesogenic may yield weight normalizing results.
It is important to note that normalization currently does not mean acquiring adequate protein intake. Protein with a complete source of amino acids is essential and a minimum of 0.8g/kg protein is considered the minimum protein requirement for sedentary individuals with increased requirements as the level of physical activity increases.
These foods, in practicality, inert either due to their chemical nature, their lack of calories and/or because they may influence satiation or meal termination but do not impact long term energy intake and fluctuations in fat mass.
The reduction of energy intake after consuming a caloric load. A food product is fully compensated if its consumption is compensated by a reduction in caloric intake to maintain maintenance calories.
Sensory Specific Satiety
The feeling of fullness or ‘fatigue’ towards eating the same food product or item due to reduced pleasure obtained from consuming it.
Food Addiction vs. Eating Addiction
Food addiction would pertain to eating a specific food and being addicted to it. However, that is unlikely the case due to sensory-specific satiety being the same in lean and obese individuals. Eating addiction, however, is more plausible as it would involve an ‘addiction’ towards eating various types of foods, perhaps due to underlying issues which may not have anything to do with the food itself.
2. Proposed Factors in Energy Intake
It is important to note that many of these factors in isolation may not play a key role but may be associated with or collectively work as a lifestyle or induce a placebo effect on beneficial results obtained.
Satiation is considered the temporary sensation of fullness that leads to meal termination. As this sensation is temporary, it does not reflect energy intake throughout the day. This also leads to the conclusion that eating more or fewer meals per day is likely insignificant in its role towards energy intake.
Satiety & Gut Hormones
Satiety is the extended feeling of fullness after satiation or meal termination is achieved. Many have proposed that this is dictated by factors such as mechanoreceptors, osmotic pressure in the intestinal system, and/or gut hormones.
The mechanoreceptors may play a role in the long term but the short-term studies of infusions are not promising. Gut hormone(Ghrelin, CCK, PYY, etc.) release does seem to be associated with intakes of various macronutrients and perhaps even inducing sensations of fullness. However, this does not reliably correspond with energy intake per day. Additionally, the amount of major satiety hormones required to reduce energy intake in humans is physiologically not possible, rendering the gut hormone signaling an unreliable way to predict energy intake. Perhaps, the gut hormones are the downstream consequence and in for the ride but in the context of modern foods, they do not yield promising results.
Micronutrient intake does not reliably predict energy intake as concentrated forms of micronutrients such as multivitamin pills or finely ground forms of foods do not reliably reduce energy intake.
We’ve found that macronutrient composition isn’t a reliable predictor of energy intake as many outlier foods concentrated and isolated in certain macronutrients(eg. Protein water, sugary sodas) favor a positive energy intake thereby mitigating the role of macronutrient composition in energy intake.
Protein Leverage Hypothesis
The protein leverage hypothesis states that increasing the percentage and/or amount of protein in food would reliably reduce energy intake. However, this has been proven false in studies that show no reduction in energy increase with reduction in protein intake while many isolated and concentrated forms of protein(eg. Protein shakes, protein water) favor a positive energy intake.
Food Volume & Water Content
Food volume on its own does not reliably predict energy intake as many foods such as cotton candy, water, and sugary sodas which are high in volume, and even weight, favor energy intake. Additionally, depending on the digestive phase, food macro, micro, and macro structures can adsorb or absorb water or other structures content to increase or decrease in volume thereby completely altering its initial volume before passage through the mouth.
Additionally, many studies conducted using water pre-loads show an inconclusive or inert role of water pre-loads before meals when it comes to energy intake reduction throughout the day.
Portion Size & Consumer Behavior
Many studies regarding portion sizes and consumer behavior were championed by many researchers, prominently by Brian Wansink. Though an interesting area of research, several studies conducted by Wansink were eventually retracted after 2017 and we do not have reliable information on portion size and consumer behavior. It is important to note that many foods are pleasing to consumers with varying portion sizes which lead to the reduction or gain in energy intake. For now, it would be safe to assume that portion size and consumer behavior are irrelevant or play an insignificant role in reducing energy intake.
Flavor Profile, Food Palatability & Hedonics
An interesting area of research that gained much interest in the late 20th century to the present was the implications of food on the brain. Eventually, many book authors and writers coined the term ‘hyperpalatability’ to denote foods that were considered “too tasty” or “too rewarding” and would lead to overconsumption.
Much of the research is rather inconclusive and is dismissed by the concept of sensory-specific satiety which, similar in lean and obese individuals, notes reduced pleasure from eating the same food. It was also noted that the capacity to terminate meals is similar among lean and obese individuals. Additionally, studies on this topic did note palate adaptability based on previous foods and flavors consumed. It is also important to note many global cuisines have varying foods with various tastes and flavor profiles with varying BMIs which aren’t suggestive of hedonics playing a key role in energy intake and obesity.
Similar to portion size, the caloric load isn’t a reliable predictor of energy intake. Many low viscosity beverages(eg. Protein water, sugary sodas) are high in calories but after consuming them show little to no energy compensation later throughout the day. This suggests a weak or insignificant relationship between caloric value and energy intake.
Maintaining chemical similarity between two compounds, it is hard to see how the source of a macronutrient or micronutrient has a drastic impact on energy intake. Depending on how a certain compound may engage with other components to dictate nutrient delivery and sensations of fullness may play a role.
Through extensive combing of studies, we’ve concluded that blood level fluctuations of insulin, glucose, free fatty acids, and glucose levels do not reliably reduce energy intake. We have noted that certain medium-chain triglycerides are fully compensated but the practicality and long-term results are not reliable.
Level of Processing
Food processing can increase the bioavailability of nutrients, create modern foods and recipes and produce safer foods for human consumption. The level of processing does not reliably predict energy intake as studies conducted with low-calorie ultra-processed foods have shown to reduce energy intake in various controlled trials. This notion is grounded in an unscientific naturalist fallacy which may lead to unsafe food consumption and may hinder our understanding of foods.
Currently, we are not aware of any evidence supporting or suggesting a direct impact on energy intake with increased or decreased electrolyte(potassium, magnesium, sodium) intake. Electrolyte salts may enhance the palatability of foods but the human palate adapts to taste components so this is likely not a major factor long term when it comes to energy intake.
There is no evidence we are aware of that shows intake of probiotics reduces energy intake in humans through an increased energy intake may occur with the intake of probiotics.
Considering the rate of obesity being variable across different cultures and countries with same-family members having different BMIs while interventions showing energy intake increase or decrease within trials without the influence of genetics, the role of genetics when it comes to energy intake is questionable and, perhaps, insignificant when it comes to large-scale population.
Types of Fat: Plant Oils, Animal Fat
Currently, there is no evidence we are aware of in human-controlled trials that suggest that the percentage of various types of fat specifically plays a role in reducing energy intake when the caloric value of each fat is factored in. The only known fat that is fully compensated when it comes to energy intake is medium-chain triglycerides.
Fasting is considered a long period without food(caloric) intake. When matched for caloric value, we are unaware of any short or long-term benefits. For some individuals, this may be a sustainable way to reduce energy intake or provide some, though questionable, therapeutic value but for a majority of individuals, long periods of not eating is not a sustainable habit.
Many non-nutritive sweeteners can be used alternatively to sugar and nutritive sweeteners to reduce energy intake. In many cases, non-nutritive sweeteners are associated with reduced energy intake and/or may play an inert role in energy intake. Some sweeteners are known to have some glycemic response while some may induce short-term or dose-dependent digestive discomfort. Some “non-nutritive” sweeteners may offer some caloric value as well.
The addition of amylase to starchy and carbohydrate-based foods drastically increases energy intake in free-living individuals. This may be applicable in countries suffering from malnutrition but in the context of modern western diets, it would favor positive energy intake.
With varying types of physical activities and the existence of outliers in each such activity, it’s hard to find causation with increased physical activity and reduction in energy intake. It is noted that with increased muscle mass, energy expenditure does increase but it may or may not be substantial enough to offset potential increases in appetite. Nonetheless, physical activity is associated with several benefits and collectively as a lifestyle change may influence energy intake.
Calories in nuts depend on the particle size of the nuts before consumption. It is noted that nuts, even when particle size is reduced, offer a strong compensatory response which involves a reduction in energy intake later despite sizable intake levels. Even under overfeeding conditions, an increased energy expenditure helps offset much of the increased energy intake of nuts. In most studies, nut intake is associated with normalization of weight and/or reduction of fat.
Cold exposure does increase brown adipose tissue which leads to non-shivering thermogenesis and enhanced energy expenditure. However, the significance of this about fat loss may be negligible while its sustainability and practicality in free-living conditions are questionable. Cold exposure may offer some therapeutic benefits which have not been a subject of our research.
Protein Shakes, Powders, and Isolates
In the fitness industry, protein isolates and drinks are considered to be leaning due to the false messaging of protein being considered the most satiating macronutrient. As noted, protein leveraging does not work and studies on protein drinks and waters show a weak to negligible energy compensation when consumed. Outside of reaching the minimum requirement of protein at 0.8g/kg and some increase due to physical lifestyles and training, it is important to note that such drinks favor a positive energy intake with little to no compensatory response.
However, as base ingredients and in conjunction with other structural and nutritive components of food, they may transition from obesogenic to normalizing or even anorectic direction.
Polyunsaturated, Monounsaturated, and Saturated Fatty Acids
From the research in human trials, when matched for caloric value, we haven’t noticed any difference in energy intake or compensatory response that differentiates polyunsaturated, monounsaturated, and saturated fats. Mechanistic studies do not translate into controlled human trials.
Vegan, Vegetarian & Carnivore
A vegan diet or food product doesn’t ensure fat loss, weight normalization, or fat gain. Many plant-based foods, because of their structure, have to be processed in order to maximize nutrient yield. Depending on the type of processing and the end result obtained after processing, a plant-based food may either be anorectic, obesogenic, or normalizing. The same principle applies to vegetarian and meat-based diets or food products.
We are not aware of any study that suggests an active and causative role of water intake and energy intake.
Sleep may have an associative relationship with energy intake and perhaps may influence behavioral outcomes but in the context of normal sleep patterns, we are not aware of any study that confirms sleep quality could establish a cause and effect with energy intake.
The presence of blood, urine, or breath ketones, do not indicate or suggest fluctuations in fat mass and impact on energy intake. Ketone presence may suggest increased fat oxidation which can be from food intake, lack of food intake, lack of carbohydrate intake, or oxidation of body fat stores. Therefore, ketone presence does not reliably predict fat loss, fat gain, or normalization of fat mass.
Nitrates can be found in various foods, from packaged goods to fruits and vegetables. There is no established relationship between energy intake and nitrate content in foods.
3. Unscientific or Non-Quantifiable Terms
Many popular food writers coined this term to explain foods that were too tasty and provided artificially heightened pleasure responses due to foods. However, this has no scientific backing and is easily dismissed by sensory-specific satiety ie. The diminished pleasure obtained from eating the same food
Vanishing Caloric Density
This term was coined by food writers to note certain foods that seem to ‘vanish’ in the digestive system while providing free calories. The term has no scientific backing in itself and no evidence exists to substantiate it.