It's quite possible that nothing helps you more than something you probably do your darndest to live without.

The feeling of doubt.

Without doubt, there is no questioning. Without questioning, there is no considering. Without considering, there is no real thinking.

Without real thinking, there is no mental or emotional growth.

But that doesn't mean you have to question everything. Some things have withstood the test of time.

Like the phrase "withstood the test of time." It's a cliché, a phrase that's become trite from overuse.

Most writers do their best to avoid clichés. But not this one. Not in certain instances, at least.

That's because sayings don't last long enough to become trite unless they're true. One such is, "You are what you eat."

If you doubt the truth to that saying which is fine; doubting is good consider that the following are just a few of the recent studies that strongly suggest otherwise.

Attention deficient hyperactivity disorder, ADHD, was rare when first diagnosed in 1987. Now, it's the most commonly diagnosed childhood mental health disorder, affecting about 5 percent of children.

While the lives of children have changed greatly over those 23 years, the question is which has triggered the increase?

A study published online this July in the International Journal of Attention Disorders suggests the blameworthy change is diet.

The eating patterns of 1800 adolescents were studied by researchers at the Telethon Institute for Child Health Research in Perth, Australia and classified as either "healthy," or "Western."

"Healthy" diets contained significant amounts of fresh fruit, vegetables, whole grains, and fish, which have higher levels of omega-3 fatty acids, folate, and fiber. "Western," diets contained significant amounts of fast foods, full-fat dairy products, red meats, and sweets, which have higher levels of total fat, saturated fat, refined sugar, and sodium.

The Western diet more than doubled the risk of developing ADHD by the age of 14 even after researchers factored in and adjusted the numbers to reflect social and other influences.

Dr. Wendy Oddy, an associate professor who worked on the study, said this to Research Australia: "A diet higher in omega-3 fatty acids is thought to hold benefits for mental health and optimal brain function [while] a Western dietary pattern may indicate the adolescent has a less optimal fatty acid profile. It may also be that the Western dietary pattern doesn't provide enough essential micronutrients . . . or that a Western diet might contain more colours, flavours, and additives that have been linked to ADHD symptoms."

The evils of the Western diet have also been linked with another recent adverse health increase: the number of young girls now entering puberty "early," sometimes by seven or eight. Reaching puberty early has been linked with an increased risk of breast cancer in females later in life.

Using guidelines called the Tanner Breast Stages to determine the onset of puberty, researchers at Cincinnati Children's Hospital Medical Center examined data of 1,239 girls and discovered that a higher percentage were developing breasts than 30 years ago.

While genes and the environment could also be responsible, Dr. Frank Giro, lead author of the study and the director at the aforementioned medical center, believes that obesity also plays a part and encourages all girls to eat a healthy diet high in fruits and vegetables.

And even for those readers who already eat well and exercise, eating even a little bit better could help improve your quality of workouts.

Research presented at the 2010 American Colleges Sports Medicine's annual meeting found that studies performed on animals reinforced the importance of humans eating complex carbs and a bit of protein within 30 minutes of exercise.

The animals who did this in the study oxidized 70 percent more fat, which decreased abdominal fat by 24 percent and increased lean muscle mass by 6 percent.

And if you truly are what you eat, you're probably a bit of what you drink, too.

A study published in the August issue of Appetite found that people who use sugar substitutes significantly reduce their total number of calories and do not suffer from hunger as a result.

Researchers gave subjects some overweight, some not aspartame, stevia, or table sugar prior to a meal. Those given one of the first two low-calorie sweeteners consumed fewer calories yet did not report increased feelings of hunger afterwards.

Other research suggests that it should be tea or coffee getting sweetened by those low-calorie products. Research from the Netherlands published this summer in Arteriosclerosis, Thrombosis, and Vascular Biology: Journal of the American Heart Association found that drinking six or more cups of tea per day created a 36 percent lower risk of heart disease when compared to drinking less than one cup a day and that drinking two to four cups of coffee a day dropped the risk 20 percent when compared to those drinking less or more than that.