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WEDNESDAY, Jan. 23, 2013 — Seven apples (or oranges, or servings of broccoli) a day might be enough to keep the blues at bay, new research in the British Journal of Health Psychology suggests.

In the study, conducted at the University of Otago in New Zealand, high fruit and vegetable intake — seven to eight total servings per day — was strongly correlated with a more positive mood in 281 young adults. To determine which came first — feeling positive or eating healthier foods — researchers ran an additional analysis that predicted mood improvements in the day following high fruit and vegetable intake as well, suggesting that healthy foods might improve mood.

One serving of cooked vegetables is only a half cup — or the amount that can fit in one cupped hand - and one serving of raw vegetables is a full cup. For the purposes of the study, fruit and vegetable juices and dried fruits did not count toward the daily total.

This is not the first study to find that upping your fruit and veggie intake from the recommended five servings a day to seven servings promotes happiness and improved mental health. In October, British researchers surveyed the dietary habits of 80,000 adults and also found that the participants' sense of well-being and happiness peaked on the days when they ate at least seven servings.

Your Daily Dose of Fruits and Vegetables

Although the U.S. Department of Agriculture recommends consuming at least five servings of fruits and vegetables every day, only 14 percent of adult Americans eat enough of both, according to the U.S. Centers for Disease Control and Prevention.

The key to eating enough is including at least one serving at each meal (researchers recommend filling half of your plate with fruits or vegetables) and consuming a wide variety of types and colors. To give you an idea, here's a sample one-day meal plan from Everyday Health nutritionist Maureen Namkoong, RD. This day of eats actually contains nine servings of fruits and vegetables and about 1,650 calories, depending on exact portion sizes".

Breakfast: 1 slice of whole-wheat toast, 2 T. of natural peanut butter, and a banana

Lunch: 1 green salad (two cups of mixed greens), topped with 4 ounces of diced

chicken, 1/2 cup each of cucumber, bell pepper, onions, and tomatoes, and 2 T. of balsamic vinaigrette salad dressing

Snack: 1 cup of raw carrot sticks and 2 T. hummus

Dinner: 1 4-ounce salmon fillet with 1 baked sweet potato, 1/2 cup of roasted broccoli, and a 1.5-ounce square of dark chocolate for dessert

- Republished with permission from EverydayHealth.com