The DASH Diet is the No. 1 diet in America, according to the U.S. News and World Report's Best Diets 2012.

Beating out Weight Watchers and the Ornish diet, DASH (Dietary Approaches to Stop Hypertension) claimed first place for healthy eating and was ranked the best diabetes diet (tying with the plan advocated by The Biggest Loser) as well.

But if the DASH Diet is one of the best weight-loss plans in America, why have so few people heard of it? What does it do? Does it have a catch, like the fatigue and mild malnutrition sometimes seen in Atkins dieters?

Find out the answers to these and more with a rundown of what to know about the new health plan. From how to get started and what steps to follow, to how it's emphasis on healthy eating may not always lead to weight loss, here are five things dieters should know about the DASH Diet.

1. The Basics of the DASH Diet

The DASH health plan actually began as a way to lower blood pressure: people were encouraged to eat more fruits and vegetables, cut back on meat and fats, and incorporate blood pressure-fighters into their systems.

By designing the diet to have a calorie deficit, however, DASH can also be used as a weight loss program, and has taken off as one this year in the U.S.

The diet requires you to eat lots of fruits and vegetables, as well as a good amount of low-fat dairy products, whole grains, fish or poultry, and nuts. In exchange, the diet advises steep cuts in foods high in fat and cholesterol as well as red meat, sweets and salt.

In addition to these food pyramid basics, however, DASH dieters must also add foods rich in what the program calls nutrients of concern, things like calcium and fiber that are often lacking in an average American's diet.

The DASH Nutrients of Concern are fiber for digestion, potassium for lower blood pressure and decreasing bone loss, calcium for strong bones, blood vessels and muscles, vitamin B-12 for cell metabolism, and vitamin D for regulating calcium and phosphates in your body.

While DASH doesn't offer a tailored exercise plan, it does offer advice for all levels and fitness goals, according to its web site DASH for Health, and encourages a steadily more active lifestyle.

2. It's Easy to Get Started...

The DASH Diet book has been praised by dieticians and everyday calorie counters as an easy program to understand.

The DASH Diet is sensible, healthy and effective, one dieter gushed on the web site's reader feedback section. The book is easy to read, understand and follow.

Another reviewer praised the book for showing portion sizes for different calorie levels, something she'd struggled with in the past. This was the first diet that made any sense, she wrote.

Nor do potential dieters need to shell out cash for The DASH Diet Action Plan, pioneered by Dr. Marla Heller. The National Heart, Lung and Blood Institute (NHLBI), which helped create the program, is offering free guides at 64 (PDF here) and just six (PDF here) pages in length, calculating what dieters should eat and their what their daily calorie count should be based on their age and exercise level.

3. ... And Harder to Stick To (or Afford).

The tricky thing about diet that actually work on changing people's relationship with food is that making those changes are a lot easier said than done.

Although DASH doesn't use a points system like rival Weight Watchers, it still demands changes to dieters' routines that aren't easy fixes and require (at least in the beginning) a lot of effort to stick to day by day.

Take, for example, May Clinic's guide to using DASH guidelines while shopping. In addition to detailed lists at the start of each week, including planning out meals, drinks and snacks, shoppers must also scour nutrition labels for calories, fat content, vitamins and minerals and protein. No pre-made meals or free weekly deliveries here.

But beyond the grunt work, there's also an issue of price. For dieters or simply those looking to get healthy, buying almost everything fresh and organic can be a big strain on a budget. Even when dining out at restaurants, the complications (and sometimes upped cost) of ordering a healthy meal can end up undoing much of the joy associated with having someone else cook for you.

In the U.S. poll, the diet scored lower for its work load and price tag, despite scoring 4.1 out of 5 overall.

4. DASH is Easy to Customize

What it lacks in initial ease, however, it more than makes up for in variety. The DASH Diet itself emphasizes color, texture and flavor variety simply by the ingredients it pushes. And in contrast to other health programs, this one's easily customizable for Kosher, Halal or gluten-free diets, as well as followers who are vegetarian or vegan.

In fact, according to its web site, the original DASH Diet was modeled off of a vegetarian lifestyle, since vegetarians tend to consume less salt and have lower blood sugars than omnivores.

5. It's a Health Diet, Not a Weight Loss Diet

The DASH Diet is undeniably the healthiest program out there. In addition to moderate weight loss and lowered blood pressure, DASH may also help lower cholestoral, according to a 2008 study from the Archives of Internal Medicine, which found the diet was associated with a lower risk of coronary heart disease and stroke in women who had reached middle age.

The 22-person volunteer panel that chose DASH as the best diet of 2012 also looked at its ability to generate long-term and short-term weight loss, with favorable results. The diet plan has no known health risks and appears to yield manifold health benefits.

The important thing to remember, however, is that the DASH Diet was not designed primarily or initially as a weight loss program, and that those who are looking to shed major pounds should take a long-term view of the program.

Because DASH rejects the idea of low-carb diets and puts its emphasis on exercise and changing people's view of their food, the results of a weight loss plan will take longer (though likely be more lasting) than a liquid diet, Atkins or pre-prepared meals from other programs.

Too, the program's recommended foods need to be followed according to their recommended servings in order for the program to actually work. Scarfing down a few more fruits and vegetables won't rock the boat too much, but eating a lot of cashews and almonds because the program encourages eating nuts might tip your calorie count for the day, even if the food is healthy.

Related Article: DASH Diet Vs. Weight Watchers, Which is Right For You?