Diets come and go, and it seems that with every passing year a new fad in healthy eating hits the headlines.

Only a few regimes manage to remain in vogue for any length of time, but one that became popular earlier this decade and which still has its adherents is the baby food diet.

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Reportedly created by celebrity personal trainer Tracy Anderson and followed by A-listers including Jennifer Aniston and Reese Witherspoon, the diet doesn’t have any definitive rules, but read on to find out how to follow it – and whether it actually works.

How does the baby food diet work?

There are various suggestions on how to maintain the baby food diet, but the general rule seems to be that one or two meals a day, as well as snacks, should be replaced with jars of baby food, followed by a full healthy dinner. Some sites suggest eating as many as 14 jars a day.

Baby foods normally contain no more than 100 calories per jar, and as they come in small amounts they help with portion control. Typically they are natural foods, free of preservatives or additives, which have been pureed to make them easy to digest.

Any baby foods can be eaten, but most online information recommends as broad a mixture of food types as possible – certainly meats for protein, fruit and vegetables.

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Can you fit the baby food diet in with other food preferences or restrictions?

Being a vegetarian or vegan on the baby food diet is fairly easy, but beware: plant sources of protein, like beans and soy products, aren't typically found in baby food, so be prepared to find your protein from other sources.

Most fruit and vegetable baby food should be free of gluten, but check labels to be certain. Some other baby food products, including cereals and meat-based foods, may contain wheat.

How easy is it to follow the baby food diet?

According to reports, not very. Of course, there are some benefits: you’ll spend a lot less time cooking, and shopping should arguably be easier – but the diet can be difficult to maintain.

For starters baby foods are necessarily fairly bland, so sticking to eating only them for any length of time can be difficult as adult tastebuds need more stimulation.

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Baby food isn’t necessarily entirely healthy either – you may not be getting the required amount of calories, vitamins and nutrients if you only eat a few jars a day, whereas if you eat as many as 14 you’ll need to be careful that you are not exceeding your recommended daily intake of salt.

Furthermore, because protein, fibre and the act of chewing food help you feel full, you may find that you often feel hungry on the baby food diet, depending which foods you choose and how much of them you eat.

Does the baby food diet work?

Some websites suggest the baby food diet is better for maintaining a healthy weight, as opposed to weight loss itself; others claim it is possible to lose as many as 7lb a week.

While small portions and largely additive-free foods should certainly keep weight down, the baby food diet may be – as mentioned above – hard to maintain; and pretty much every health practitioner will tell you that the best way to lose weight and keep it off is to find a healthy eating plan you can stick with for the long term, and to exercise regularly.

When trying any new diet, the American Academy of Nutrition and Dietetics suggests asking yourself: “Can I picture myself eating this way forever?”  If the answer is no, you can safely assume that the diet should only be used as a quick fix or as a kick-start to a more varied eating plan.