On face value, it seems obvious that simply substituting fruits and vegetables for higher-calorie foods will increase vegetable intake as well as reduce overall caloric intake. But while we all know and understand this concept, the reality is Americans are eating fewer fruits and vegetables every day.
According to a 2007 study from Johns Hopkins University, just 28 percent of U.S. adults are getting their two or more servings of fruit a day, with a mere 32 percent eating the three or more recommended servings of vegetables a day. This is even more alarming when you realize that dried fruit and 100% fruit juice count toward the fruit tally, and French fries are included in the vegetables!
What is going on?!? According to a recent study, the answer comes down to taste. 
With the easy availability of highly processed foods, Americans seem to have developed a taste for sweet, salty and often fat-laden cuisine. As a result, we tend to consume more energy-dense (i.e. high calorie) foods rather than lower calorie options like fruits and vegetables.
Over time, this constant consumption of sweet and salty foods has altered our taste perception, completely negating the other two tastes: sour and bitter. In plain terms, that means that after years of eating chips and cookies, many people simply cannot stomach the taste of plain old apples or broccoli.
But what if you could “hide” veggies in more commonly consumed foods? Would people know, and could you get them to inadvertently up their vegetable intake?
That’s exactly what one study from the American Journal of Clinical Nutrition set out to discover.
Not Your Mother’s Mac and Cheese
Researchers at Pennsylvania State University recruited 41 college students aged 20 to 45 years old to eat three specially prepared meals one day a week for three weeks. Breakfast included carrot bread, strawberry yogurt, sliced peaches, and coffee or tea.
Lunch was macaroni and cheese, buttered broccoli, grapes, roll and chocolate pudding. Dinner was a chicken and rice casserole, buttered green beans, mandarin oranges, roll and pound cake. Participants also had an evening snack that included fig cookies, popcorn and baby carrots.
On test days, the vegetable content of the carrot cake, macaroni and cheese and casserole were varied. Participants may receive a serving made with standard ingredients or one of two reduced versions (either 85 percent standard ingredients or 75 percent standard ingredients). In the 85 percent condition, three times more vegetables were included, while in the 75 percent condition, 4.5 times more vegetables were utilized.
In the case of the carrot bread, pureed carrots replaced some of the other standard ingredients. For the macaroni and cheese, pureed yellow squash was used, while pureed cauliflower was used in the chicken and rice casserole.
As a result, in the 85 percent condition, total calorie intake decreased by 202 calories. In the 75 percent condition, total daily calorie intake dropped by 357 calories. Additionally, vegetable consumption jumped from 270 grams in the standard meal plan to 487 grams in the 75 percent condition. Plus, those in the 85 percent condition ate an average of one additional serving of vegetables per day for, while those in the 75 percent condition consumed two additional servings of vegetables a day.
Of course, this was all to be expected. It doesn’t take a rocket scientist to figure out that calories would go down, and overall vegetable grams and vegetable servings per day would increase when you add additional vegetables to a meal. The real question is… how did it taste?
Apparently, not that different. In the case of the macaroni and cheese, 72 percent of the people liked the taste of the non-vegetable dish, while 68 percent liked it with some squash and 66 percent liked the version with the most squash.
But, most interesting is the carrot bread. Sixty-three percent liked the basic recipe, but 76 percent liked it with more carrot added, and 77 percent liked it with the most carrot added to the bread. The taste apparently was improved by the addition of more carrot.
This is particularly amazing when you consider that 36 percent of the participants said that they strongly disliked yellow squash, while 28 percent had a strong dislike for cauliflower. And, yet, they gobbled up the dishes with those exact vegetables added to it.
While this study proves a rather obvious point, that hiding vegetables in your meals helps reduce calories and ups vegetable consumption, it also shows that you can reintroduce vegetables that had been on your “no way” list without even tasting them.
So, first things first. Discover what vegetables you like and eat more of those rather than trying to force down foods you dislike.
Next, keep more of them on hand. If you like them, slice up (or buy pre-sliced) peppers, celery, carrots, broccoli and cauliflower for easy use. You can eat them raw with ranch dressing, hummus or any preferred dip of choice. You can also steam for a quick side dish.
If your veggie palate (or that of your kids, spouse, etc.) is even more limited, invest in a cookbook such as Deceptively Delicious by Jessica Seinfeld. While it’s not necessarily the healthiest cookbook on the market, it does do a good job of getting hidden vegetables into common dishes such as meatloaf, pizza, chili, tacos, pancakes and even brownies.
 Blatt, AD, et al. Hidden vegetables: an effective strategy to reduce energy intake and increase vegetable intake in adults. Am J Clin Nutr. 2011 Feb 2. [Epub ahead of print]