The other day I did something I’m not proud of. After ordering a healthy, kale-based drink, I fired out a picture to Instagram and tagged it #greenjuice. It’s not the first time I have shared a photo of me “being healthy”, but I have decided that it will be the last. I have realised, ironically, how unhealthy this is.

Millennials are constantly uploading similar photos of themselves to social media: pictures that show us eating a vegan snack, stretching in yoga pants or showing off honed abs. That’s because one of the defining characteristics of our generation is a concern with wellbeing. The Nielsen Global Health and Wellness survey of 30,000 consumers in 60 countries found that 32% of millennials would willingly pay a premium for “healthier products” compared with 21% of baby boomers (the trend continues with even younger consumers, with 41% of those under 20 saying they’d willingly pay more).

According to market research company Technavio, millennial health concerns have also contributed to the growth of the gluten-free food industry. And studies show our love of keeping fit. A Nielsen: Les Mills global consumer fitness survey in 2013 found more millennials are now doing gym-type activities than any other generation.

But I am convinced that all this striving for healthiness raises our anxiety levels (who can live up to the example of raw and vegan food blogger Deliciously Ella?). And we already have enough to worry about: millennials are more stressed than any other current living generation, according to a survey conducted by the American Psychological Association and Harris Interactive. In the UK, research from Aviva’s new Health Check UK report found something similar: more than a quarter of 18- to 24-year-olds say they have suffered from anxiety in the past year, compared with 23% of 35- to 44-year-olds and 11% of people aged over 65. What’s more, the number of 16- to 25-year-olds looking online for help with anxiety is on the rise, according to the charities Anxiety UK and YouthNet.

I am not suggesting that there is anything wrong with being healthy. I love looking after myself. I run, go to the gym and do yoga several times a week. I also eat well. As someone who has suffered from chronic anxiety in the past, I find that keeping fit and sticking to a healthy diet are key to maintaining good mental health.

But when you start to feel like fitness is making demands on you that you can’t possibly meet, it can become a problem. We need to resist this imperative to be the healthiest we can possibly be. It’s no longer about just eating your five a day. It’s also about having a stash of cacao nibs or chia seeds in your cupboard, and working out every day. And when this is thrown in our faces on social media, we can end up feeling guilt and despair just for enjoying a chocolate bar.

A female friend of mine summed it up recently: “If these women can look like this, why can’t I? I love exercise and eating healthily, but between work and a social life, I just don’t have enough time. It makes me quite self-critical and anxious.”

A male friend said he felt the same, lamenting the fact that the previous generation drank and smoked too much, and ate all the good (bad) food, while he feels guilty for eating a bacon sandwich. His comments were based on recent reports from the World Health Organisation that processed meats are as bad for us as tobacco.

What’s more, avocado salads and superfoods are expensive. Living healthily has become a form of conspicuous consumption, and when we can’t afford the latest blenders and gadgets, we’re made to feel like failures. People are also showing their fitness credentials through workout sessions such as 1Rebel UK and Barry’s bootcamp. These places offer group training for £20 a pop. And it’s not just classes that millennials are paying for, they’re also shelling out for gym merchandise – which can range from skimpy crop tops to fancy water bottles and post-workout shakes/ juices. There is a great deal of pressure to spend loads on all the gear and turn up – raw food bar in hand – looking like you’ve just walked off the set of Made in Chelsea.

For some millennials, our obsession with clean living has become a problem in the form of orthorexia nervosa (defined as a “righteous fixation on eating healthy”). Jordan Younger, former vegan blogger, has spoken out about this. During an 800-calories-per-day juice cleanse her hair was falling out, her skin was blotchy and she stopped having her period for sixth months because of a vitamin deficiency. This is an extreme example, but it shows that the reality behind these social media lives isn’t always what it seems, and that perfect healthiness – like perfect anything – is unachievable.

In a paradoxical way, our drive to be healthy may actually be a product of our anxiety. We sometimes seem to have so little control over our lives – our finances and work-life balance, where we live, our relationships – that being healthy is one of the few things we can determine for ourselves. For those who feel they are stagnating in their career and cannot afford to buy a home, focusing on health and fitness is a way to excel.

But let’s be honest: a fantastically healthy lifestyle can be bloody stressful – and dull. Who wants to worry about whether or not to have a croissant? Why are we spending so much on seeds? I’m really keen to hear what other people think about this and welcome comments. My own view is that too many young people are now battling with extreme perfectionism about food when they should be seeking balance in both their diet and their lives. As a wise person once said to me: if you want the thing, eat the thing. Life is too short.