Americans certainly like to have choices. We went from just a handful of TV channels 25 years ago to hundreds of options today. Ditto for grocery stores, drugstores, and even fast food restaurants.
In fact, food may be the place we like variety the most. However, research has shown that too much variety, especially of high-calorie foods offered at any one meal (think buffet), leads to increased food and calorie consumption.
This is due to something called sensory-specific satiety. The concept is that when a lot of different foods are offered, switching from one type of food to another keeps the meal “going” if you will… and keeps you eating.
Given this concept, researchers wondered if the same rule applied to vegetables.
More Veggies Equals More Veggies
To determine the effect that a greater variety of vegetables would have on actual vegetable intake, researchers set up a study with 66 adults who ate four different meals one day a week for four weeks. At each of these lunchtime meals, participants ate one of four meals:
1. Pasta with tomato sauce and Parmesan cheese and broccoli with butter
2. Pasta with tomato sauce and Parmesan cheese and baby carrots
3. Pasta with tomato sauce and Parmesan cheese and snap peas
4. Pasta with tomato sauce and Parmesan cheese and equal amounts of all three vegetables
On each test day, all participants were asked to rate their hunger, fullness, thirst, nausea, and how much they thought they would be able to eat at that meal. After a quick taste test of the meal, they were asked to rate the taste of the meal. They were then served the lunch for that day.
Immediately following the meal, participants once again rated their hunger, fullness, thirst, nausea, and how much they thought they actually ate. After the last test meal on the fourth week, they were also asked to rank the three vegetables in order of preference.
Researchers calculated the amount and total calories of each meal before it was served and after the participants had finished. They found that vegetable consumption was significantly affected by variety. In fact, participants ate nearly half a serving more of the mixed veggies than any one single vegetable offered.
This remained true even when the researchers took into account people’s personal preference for one vegetable over another. Of the 66 subjects, 41 liked the broccoli best, followed by peas with 14, and carrots with 11 supporters. When mixed consumption was compared against a person’s personal favorite, they still ate one-third more when offered the variety.
The best part was that, even though the participants ate more when offered the mixed vegetables, because the choices were lower calorie and higher fiber, their overall caloric intake did not increase by much. Additionally, there were no significant changes in subjects’ ratings of hunger, fullness, thirst, nausea, or projected consumption either before or after the meals.
Researchers did note that one key to the success of the test was that each vegetable varied in color and texture, as well as shape and taste. And, of course, the butter on the broccoli didn’t hurt.
Based on these results, researchers concluded, “Increasing the variety of healthy low-energy-dense vegetable at a meal can be used strategically to increase their intake.”
Mix It Up
There is no question we all need to eat more vegetables. This study gives us a few great tools to lean on. First and foremost, give yourself lots of options to choose from at a meal. Second, play with seasonings.
For the first suggestion, here are a few ideas to get you going:
1. For breakfast, make an omelet with peppers, onions, mushrooms and eggplant.
2. For lunch, toss spinach and chopped romaine lettuce with scallions, cucumbers, celery and water chestnuts.
3. At dinner, keep your protein portion to five or six ounces and serve with pureed cauliflower, steamed broccoli and snap peas.
4. For a snack, try babaganoush (eggplant based) with baby carrots, endive and celery.
As for seasoning, season your veggies with herbs, infused olive oil, and fragrant spices, such as garlic and ginger.
 Rolls BJ et al. Variety in a meal enhances food intake in man. Physiol Behav. 1981;26(2):215-21.
 Rolls BJ. Sensory-specific satiety and variety in the meal. In: Dimensions of the Meal: The Science, Culture, Business and Art of Eating.Gaithersburg,MD: Aspen Publishers, Inc;2000:107-16
 Meengs JS et al. Vegetable variety: an effective strategy to increase vegetable intake in adults. J Acad Nutr Diet. 2012 Aug;112(8):1211-5.