A commonly used phrase when referring to nutrition is “a calorie is a calorie,” which can be misleading. A calorie is a measurement of energy; it’s the amount of energy needed to raise one gram of water one degree Celsius.
Over time, however, calories have come to be associated with human biology, not just with energy measurement. It is true, from an actual energy standpoint, that in a closed loop system all calories are equal. It’s when we look at what happens to a calorie after it’s ingested, that we start seeing some important differences that depend on the source of the calorie.
Although all foods provide energy to the body, foods also deliver nutrients, influence hunger, and trigger different hormonal pathways.
Consider 100 calories derived from table sugar compared to 100 calories derived from olive oil; these calories have different speeds and pathways of digestion, trigger different hormonal pathways, and can have different impacts on weight management and overall health.
So when considering calories, it makes more sense to not just consider the total amount of energy derived from a calorie, but also daily nutrient needs. Dietitians recommend a focus on the nutrient quality of calories, not just total calorie quantity – an approach referred to as nutrient density.
Nutrient density is an approach that promotes getting as much out of total daily calorie intake as possible, and striving to meet not only energy needs but also vitamin, mineral, and other nutrient and biological needs from those total calories.
It’s a myth that there is one perfect diet. Our nutritional needs are as individual as our fingerprints, so understanding what causes a person’s nutritional needs to be different can help that person choose the best combination of foods and supplements that meets their needs.
Factors that influence energy needs include exercise, recovery, illness, and metabolism, all of which have an impact on an individual’s calorie requirements. Stress levels, hormone fluctuations, and even environmental pollutants can alter an individual’s specific nutrition needs.
Careful attention to the nutrient density of daily calorie intake can determine gaps in nutrient intake and identify nutritional supplements that can complement the diet.
When adjusting calorie intake for daily activity, many active individuals underestimate the number of calories and added nutrients that are necessary to accommodate their activity level, while; ironically, many inactive persons consume more calories than required for their activity level.
Drinking sufficient water daily will increase energy, improve the appearance of the skin and fascia, keep muscles and joints lubricated, help prevent brittle hair and nails, improve overall health, and help prevent overeating.
Being sufficiently hydrated substantially impacts mental ability and overall physical performance. Hydration needs vary from person to person based on activity level, ambient temperature, altitude level, and numerous other factors.
The rule that the body needs eight 8-ounce glasses of water a day is not based in science and no one seems to know where the rule came from, other that it is easy to remember.A more person-specific recommendation would be to drink one-half to one ounce of fluid per pound of body weight per day. So, someone who weighs 190 pounds should be drinking a minimum of 95 ounces of liquid per day.
We are all familiar with the FDA-imposed phrase “Based on a 2,000 calorie diet” printed on Nutrition Facts labels for foods and Supplement Facts labels for supplements. As noted earlier, calorie requirement varies from person to person; so, a 2,000-calorie daily intake is meant to serve as a guideline that is appropriate for most healthy people.
The FDA-imposed calorie amount is used to standardize a percent daily value of various nutrients into a consistent number. The FDA has established Recommended Daily Intakes (RDI) for each of these nutrients and requires food and supplement labels to show the percent of each nutrient’s daily value (%DV) that is consumed per serving.
The confusion occurs when a person assumes the Recommended Daily Intake will meet their specific needs.
The FDA’s RDI is the amount of a nutrient needed to meet the needs of 98 percent of healthy Americans across all demographics. The RDI intentionally casts a wide net to cover the needs of the largest number of people but the RDI does not consider multiple factors that might require a higher intake of certain nutrients.
So the more you know about yourself and your individual nutrition needs, the better you can tailor your daily nutrient intake.