Writing about nutrition and exercise

You don't need any qualifications. I know plenty of writers who do it out of personal interest with no more credentials than that. That said, the more credentials you can show, the better; it certainly doesn't hurt!

You might try starting a blog or something similar with a nutritional/exercise theme.
If you can maintain a following editors might be interested. And it would also be good practice.
Pitching articles to magazines is another way to start out. Start with the best magazines in your area and work your way down.
I imagine most of them will be more interested in your writing expertise and experience than your sciencey background, and both of those might be thrown out the window if you have an excellent hook.

I'm not an expert though, so take what I say with a grain of salt. Good luck

The writers you see working in areas like health, technology, finance, etc. don't necessarily have professional experience in those areas (though many do).

What they all share (in addition to writing ability) are fantastic research skills.

They know where to find reliable information on scholarship, trends and issues in their chosen fields, whether through print sources or credible experts.

As you launch your health writing career, familiarize yourself with the major peer reviewed journals in your subject-matter area and learn to access them online. Your local library can be a great resource for this.

Also, start identifying credentialed experts who can serve as your go-to sources.

While not necessary, being a certified trainer/med student is definitely a bonus -- and the longer you are at it, the more attractive your credentials will be to potential clients.

This is a great reason to position yourself as an expert through blogging, participating in your professional organizations, presenting at conferences and working to increase your visibility and credentials.

There is huge demand now for writers who are also experts in their subject matter.

As a member of the Guild of Health Writers in the UK, I have to say that understanding of health issues and nutrition is vitally important to write on the topic. Readers know a lot about their own conditions in these days of Google, and the slightest mistake will attract letters to your editor and you won't get commissioned again! I have 6 qualifications in medicine, nutrition and nutritional medicine and worked as a doctor for 15 years, yet I still check, check and double-check before filing copy! You can always quote experts to fill out a subject you don't know a lot about. Good luck!

Cambridge's post just made me think of The HittList.

It's a fantastic (and free) job resource for medical writers, and it's mostly aimed at folks with a career background in medicine (doctors, nurses, pharmacists, researchers, etc.).

I've been a subscriber for several months, and I've never yet seen a job on it I'm qualified for! But I like reading about all the opportunities that are available to medical writers -- beyond articles for mags and websites.

You don't need any qualifications to write about nutrition and fitness. To an editor, it's more important to be able to research and craft a good article than to have a background in the area. (I've seen many writers with credentials whose articles are poorly written.)

If you don't have a background in the health industry, you need to be able to research the topic, track down the best experts for the story, understand research study articles, etc. I have no training in any health field and instead rely on extensive research for all health articles.

That said, if you're pitching a publication that's more scientific than consumer-based, you may have a harder time nabbing a freelance spot without an MD, PhD, or RD after your name. That doesn't mean you shouldn't try. Just make sure you show your ability to research and write in the pitch.

I've written quite a few articles related to health and nutrition and I don't have any special qualifications. If you want to specialize in this area, I have to say, I think it's a very lucrative niche. The possibilities are really endless. You could write for magazines targeting a lot of different audiences (men, women, teens, retirees,). Also, most general interest pubs have at least some content related to health, nutrition, and/or exercise.

Also, think about copywriting for hospitals, universities, health companies, etc.

I would not go after a personal training qualification just for the sake of writing about the topic. I'd say start researching and pitching ideas to magazines and build up from there. If you get enough published in the area, you'll become an "expert" and it can be your "beat."

Good luck!