Calorie or energy density is about the number of calories per gram of food. For example, one gram of celery contains one-fourth of a calorie and one gram of peanut butter contains five calories.
How it Works
Foods that are high in water content are usually low in energy density, such as fruits and vegetables, which are high in fiber content. Low energy density food helps feel full while being low on fat and calories. People who consume low energy density food enjoy eating larger amount of food with fewer calories than those who consume high energy density food, as found out by Dr. Rolls’ research team at Penn State. Low energy density foods also provide different micronutrients such as calcium, potassium, iron, folate, vitamin A, B6, and C.
Why it Matters
Even though portion control is important, it is hard not to keep eating as long as hunger is not eased. It is good to find food that can help feel full and satisfied without exceeding calorie budget and fat content. Low energy density food helps consume larger portion of food to feel full and satisfied for lower amount of calories and fat.
Why it is not Perfect
The problem with low energy density food is that it does not help consumers differentiate between good fat and bad fat or good and bad carbohydrates, as pointed out by Professor P. K. Newby at Boston Medical Centre. Despite having same energy density, polyunsaturated fats and monounsaturated fats have positive effects on body unlike saturated and trans-fats that are harmful for human body. The other thing is that low energy density is not always very nutritious.
Categories of Energy Density and Consumption
Based on energy density, there are four categories of food. Very low energy density foods: Foods that contain 0 to 0.6 calories per gram are very low energy density food and safe to consume in large amount not needing to care much about portion control.
Low energy density foods: Foods that contain 0.6 to 1.5 calories per gram are low energy density food. Portion size does not matter much.
Medium energy density foods: Foods that contain 1.5 to 4.0 calories per gram are medium energy density food. It is OK to consume food in this category in moderation.
High energy density foods: Foods that contain 4.0 to 9.0 calories per gram are high energy density food. It is a good idea to replace food in this category for foods in first two categories. While consuming high energy density foods, portion control is hugely important.
Nutrient density is about how much nutrients such as vitamins, minerals and antioxidants are contained in food. Nutrient-dense foods contain large number of nutrients and few calories. An exact formula for nutrient density is yet to be sorted out. However, it is very important topic when it comes to health and disease prevention.
How and Why it Works
According to some nutrition experts, food should contain at 1.5 times more nutrients than calories. A scoring system known as Naturally Nutrient Rich (NNR) has been developed by Drewnowski to help determine nutrient-to-calorie ratio of foods.
NNR index is based on 16 nutrients, which include zinc, potassium, monounsaturated fat, vitamin E, vitamin D, folate, vitamin B12, riboflavin, thiamine, vitamin C, Vitamin A, iron, calcium, protein, vitamin B5 and fiber.
NNR score ranges from 2 to 1000. Foods such as spinach, liver and broccoli are on the high end of the range. Fried chicken, crackers, and soda are on the lower end of the range. Over 100 is good score and over 250 is excellent score, as pointed out by Drewnowski.
Why it Matters
The concept of nutrient density allowed foods to be understood by presence of beneficial nutrients. Food choices are not just to be made on the basis of calories. Nutrient-density ratings can also help make better food choices. Some high energy density foods also have high NNR score, such as nuts, avocado, legumes etc.
Why it is not Perfect
Nutrient density lacks consideration of bioavailability of nutrients, organic nature or freshness of food. It does not deduct points for dietary cholesterol, saturated fat and added sugar. Wholegrain foods are healthy but score low on the nutrient-density scale. Applesauce or raisins scores lower on the nutrient density scale than potato chips.
How to Apply NNR
NNR of all foods may not be readily available. It has to be calculated by in individuals on their own. However, consuming non-fat and low-fat dairy products, whole grain, colorful fruits and vegetables should be fine. The main point to keep in mind is to find foods that are high in nutrient density and low in energy density. Below are NNR scores for some food.
Fruits with NNR score (100-250) include plums, avocados, nectarines, peaches, watermelon, blackberries and raspberries. Fruits with NNR score (250) include tangerines, apricots, mango, orange, kiwi fruit, grapefruit, strawberries and cantaloupe.
Vegetables with NNR score (500-1000) include cauliflower, V-8 juice, iceberg lettuce, sweet potatoes and green peppers. Vegetables with NNR score (1000) include broccoli, mustard greens, romaine lettuce, spinach, pumpkin, carrots and red peppers.
Meat and fish with NNR score (100-250) include shrimp, cod, eggs, pork, lamb, salmon, beef chuck. Meat and fish with NNR score (250) include canned tuna, snapper, beef sirloin (lean), lean ham, mackerel bluefish etc. Meat and fish with NNR score (1000) include chicken liver, beef liver, clams and oysters.
Dairy products with NNR score(100-250) include mozzarella, cottage cheese, whole milk, low-fat yogurt, two percent milk, one percent milk etc. Dairy products with NNR score (250) include nonfat yogurt and skim milk. Grains with NNR score (100) include cereal bar, waffle, bagel, oatmeal.
Last update: June 15, 2017 02:46:02 pm