And they're probably on to something here. In a recent study done by Brown University, people trying to lose weight by eating prepared meals lost an average of 31% more weight than those who prepared their own meals.

If you're thinking about using a diet delivery service to lose weight, there are several things you need to know before you buy. This article will help you know what to look for, what to expect and how to find the best service for your lifestyle.

First of all, what is a diet delivery service?

In general, diet food delivery services prepare diet meals for you and ship them to your home either once a week or once a month, depending on the type of food. You then have all your meals ready for you, portioned out and all you do is prepare and eat. Many services also offer some type of online or phone help, meal planners, starter kits etc.

The advantage is that you don't have to do all the planning, preparation, shopping etc. You just eat and the weight comes off. It's simple, easy and the meals are prepared by experts so they can be really delicious.

Plus diet delivery is now much more affordable than it used to be - around $10-$25 a day. This is about what most people spend on food a day anyways.

What types of delivery services are available?

There's lots of variety here. Some delivery services prepare meals that are based on a specific diet (for example - the Zone diet). Others offer you a choice of plans (like a low fat plan, a low carb plan or a diabetic diet plan.)

Regardless of diet type, most services are really based on low calorie, portion controlled meals designed to help you lose 2-5 pounds per week.

What kinds of meals can I choose from?

Meals range from simple snacks (Apple Cinnamon Oatmeal or Caramel Nut Bars) to gourmet chef-prepared entrees (Black Angus Prime Rib Of Beef With Baked Potato, Sour Cream And Sweet Bell or Asian Spiced Duck With Greens) depending on the plan.

Plans usually offer a pretty good variety of meals as well, with many meal delivery services changing their menu every four weeks. Others offer hundreds of meals options and you choose what you want to eat yourself.

If you find you don't like what's on the menu, many programs will let you substitute a different meal for a small charge.

How many meals per day?

In general most services offer you breakfast, lunch and dinner. Some however will only offer lunch and dinner.

Others will offer snacks as an added cost whereas others will offer snacks included. Be sure to factor this into your price comparisons depending on what you want.

While most delivery diet services offer a 7 day plan, others also give you the option of a 5 day plan (so you can take the weekend off).

This is a great convenience for those who want their diet meals delivered to their office during the week. In general you'll be paying less per week however price per day on these plans is pretty much the same as a 7 day plan.

Do I get any help or support while losing weight?

This may not be a feature that you need, however some people do like extra support while losing weight. For example some services offer you online help like message boards, chat rooms, meal plan trackers, diet tips and articles, etc.

Some services also offer phone support from dietitians and counselors. Many will also send you a starter kit with your first order which can include meal plans, tips etc.

How much can I expect to lose?

While results will depend on your personal situation (age, gender, level of activity, body composition), most diet delivery clients lose from 2 - 5 pounds per week.

With most plans you're also eating from 3 - 6 times per day so you don't get hungry and you also help keep your blood sugar levels stable. The meals are also usually planned out by dietitians so you'll be getting the proper balance of nutrition, fat, fibre, protein, etc.

As a result many people report not only losing weight but feeling healthier and more energetic as well.

So those are the main features when choosing a diet delivery service. The great news is that diet delivery is getting better and better each year (more affordable with better tasting food!). Keep these points in mind when comparing delivery services and you're guaranteed to be off to a great start with your weight loss plan.