Fad Diets: Are They Sustainable?

Green smoothie drink from above.

Right now everyone's talking about keto and Whole30, but remember the master cleanse? Atkins? Oprah's liquid diet? The grapefruit diet? Each one had its moment in the sun, and in a few years there will be a new diet that everyone is trying. 

We get the appeal. 

"Everyone wants to find that one diet that helps them succeed," says Laine Lum, dietitian at the OHSU Center for Women's Health. "Fad diets usually market themselves as effective and fast, and we all want to see results from our efforts right away." 

Couple this with the heavy marketing of fad diets, and the comradery dieters feel with friends or on social media, and it's an exciting wave to ride. But the thing about waves is that they tend to break.

Small changes

That's why Lum recommends you stop dieting, and instead look at what changes you can make in your habits that will last. "Don't underestimate the power of small changes," she says. "What will happen if you make one small shift this week to make your body feel healthier?" 

Replace soda with water. Pack your lunch instead of buying it. Add a fresh vegetable to your dinner each day. Small incremental changes can work because they are less restrictive and can be more easily folded into your daily routine. 

But we also know that restriction can be appealing. After all, it takes the guesswork out of nutrition and sounds so simple. Popular diets are usually black and white –eat lots of this, and never eat that. Often whole food groups are completely off the table. Short-term, this can lead to weight loss. 

But sustained weight loss and improved health require long-term change, and living with extreme restrictions is hard to do for long. Most people fall off the bandwagon eventually. 

"People love black and white, but nutrition is really so many shades of gray," says Lum. "We have to learn to work with that." 

Potential harms

There may be physical health and safety concerns associated with the latest fad diets. The truth is that we just don't know. No long-term studies have been conducted on Whole30 and studies of the keto diet have focused on people with epilepsy whose diets have been strictly monitored in lab settings. 

We do know that fad diets can cause serious psychological harm, and women are particularly susceptible. "The restriction mentality that is key to virtually all fad diets causes feelings of anxiety, guilt and failure for women who fall off the diet or eat the 'wrong' thing," says Lum. These feelings just get worse over time, as women try fad diet after fad diet. 

Considering a diet?

Ultimately, it's your body, and you can (and should) decide what and how you eat. Not all fad diets are equal, and some may be helpful to you, especially short-term. The research-based, personal support that dietitians offer can really help you decide. 

"Women are constantly told their bodies aren't good enough, and bombarded with fads and advertising promising to fix them," Lum says. "At the Center for Women's Health, we offer a safe place for them to let that go and make choices tied to their own needs and life." 

There are several signs that a diet is unlikely to be sustainable or lead to long-term success: 

  • It cuts out entire food groups. Eliminating whole groups of foods is incredibly restrictive, making it tough to sustain. If you think you might have a food sensitivity, eliminating whole food groups may not the best way to identify it. A dietitian is best equipped to help you create a personalized plan.  
  • It's meant to be short-term or a 'reset.' Unless your goal is to lose weight now and gain it back later, a short-term diet doesn't make sense. 
  • It requires you to spend a lot of money. You shouldn't need special supplements or equipment to eat a healthy diet.
  • It's described as easy, magical, or a miracle. There's just no such thing. 
  • You just don't think you could stick to it. This is key. Be honest with yourself about what you need and want, and don't set yourself up for failure. 

"It almost doesn't matter which fad diet we're talking about. It's the idea that you need to go on a diet in the first place that needs challenging," says Lum.  

Instead, make small changes in your habits that you can sustain. Take the time to get to know yourself and what your body needs to be healthy. And allow yourself a bit of what you crave –be it chocolate or potato chips –occasionally and in moderation.