This past weekend, I sat down at my computer hell-bent on writing this post. I knew I couldn't about write about just anything - not for my first real post on Scientific American. I mean, sure, I've written for the guest blog a couple times, but this is different. This is my blog. I have been obsessing about this post for weeks. Without realizing it, I was standing in front of the thickest writer's block I've ever seen, a wall so dense that I spent all weekend thinking about this post and still got absolutely nowhere. Suddenly, there I was: less than 12 hours before my post was to be published, and not a single word of it written. I just needed a topic, I figured. A really, really good topic.

I named this blog "Science Sushi" for two reasons. The first was that I wanted an image that would explain how interesting and great science can be when it's kept simple. No over-inflated results, no tenuous connections to barely-related concepts - just the research, all by itself, stripped of the scientific jargon that usually makes it inaccessible. The word "raw" kept coming to mind - that I reveal the "meat" of a study, or expose its "tender flesh." At some point, while throwing those words around, I imagined a plate of nigiri, but overlaying the rice were atoms and animals and all the cliche images of science instead of raw slabs of fish. Suddenly my brain was filled with visions of hand rolls bursting with DNA helices and gene sequences served alongside an Erlenmeyer flask instead of a tokkuri of sake. The visual was too powerful to ignore. So, Science Sushi it was.

Of course, the second reason (and probably the reason why the words "raw" and "tender" magically transformed images of science into nigiri and temaki) is that I love sushi. No, not love - love is what I feel for my job and my family. The emotion I feel towards sushi is such a deep passion that I don't have a good word to describe it. It's the first thing I think of when someone asks what my favorite food is, or what I'm in the mood for. I could eat it at every meal and never grow tired of the sweet taste of tender raw fish and sticky rice with just the right touch of shoyu and wasabi.

Duh!, I thought to myself, that's what I have to write about! As I sifted through idea after idea, it just seemed entirely too appropriate that this post focus on the food that inspired my blog's title and that has such a special place in my heart.

My favorite food has an interesting past. While we now think of the freshest seafood neatly wrapped in rice and seaweed, sushi began as a way of preserving fish. Early Southeast Asian peoples realized that if they packaged salted fish in fermented rice, it kept for a long time and could travel inland. That's where sushi got it's name - the word comes from "zushi" which meant "sour-tasting" in an archaic language form. It wasn't until the 19th century that nigiri was created and fresh fish became the norm. Even still, sushi was mainly a Japanese dish - only at the end of the 20th century did sushi begin to go global. Now, sushi restaurants are common worldwide, and in some areas, like here in Hawaii, they are found on every corner next to Starbucks.

Why did sushi become so popular? In part, the onset of modern technologies like jumbo jets allowed globalization of fisheries in an unprecedented way. Fish caught on one end of the world could suddenly be sold 'fresh' on the other. The other part, of course, was good marketing. In the 1970s, Japanese culture and cuisine was sold to the world as the epitome of sophistication and health. As developed nations started to feel the economic weight of rising obesity rates, healthy foods became more and more popular - sushi among them. Nutritionally speaking, it's well established that fish is one of the healthiest sources for protein and is also conveniently packed with Omega-3 fatty acids and other good fats. Rice is one of the better forms of carbohydrates out there, and even the seaweed that wraps sushi rolls, called nori, is full of soluble dietary fiber.

Of course, that's not to say sushi is always great for you. Like any food, it depends on the volume and kind. Tuna and other large, predatory fish are not only good sources of protein, they contain more than the recommended dietary dose of mercury, a potent toxin. Furthermore, eating any raw fish is a bit of a gamble, as raw seafoods can contain an impressive variety of tapeworms, nematodes, flukes and other parasites that cause disease in humans.

It's not that I'm trying to scare you out of eating sushi - clearly, all the knowledge in the world hasn't scared me. No, if only eating sushi were such a risk that more people avoided it. Our sudden appreciation of Japanese cuisine has had catastrophic affects.

As an article in TIME yesterday pointed out, fish are the last wild food. We once turned to the wilderness for all our meat. A few centuries ago, when we gazed out across the American prairies, we were overwhelmed by the seemingly endless supply of meat in the form of the buffalo. There were, quite literally, tens of millions of them. But even tens of millions were no match for human hunters, and what once was a sea of shaggy beasts dwindled to a handful of isolated populations on the verge of extinction.

Our approach to the endless bounty of the sea was no different. The oceans just seemed so deep that it was hard to believe that we could ever pull the last of a species from the vast watery abyss. Yet in the past century or so, fishery after fishery has collapsed, leaving our seas empty in comparison. You might not have noticed fewer fish in your supermarket, but according to the U.N. Food and Agricultural Organization, 70% of global fish species are overexploited or depleted. The rise in popularity of sushi furthers this trend, and prime sushi species like the beloved tuna are the latest casualties of our inaccurate view of the oceans.

The decimation of so many fish species has made us sadder but also wiser. Now we realize that we are (to steal from the recent documentary's title) at 'the end of the line' when it comes to the world's fish. It seems like overnight, sustainable seafood has become the new fad for consumers and the new focus of conservation organizations.

Management and government oversight, however, has yet to catch up with the sustainability trend. Tunas, for example, are knowingly overfished, and even still, members at the recent CITES meeting rejected legislation that would have limited the trade of tuna between countries. The EU, at least, is vowing to try and reform - they hope to make their fisheries sustainable by 2015 - if that's not too little, too late. To be fair, this would be is a step up from the dreadful way they have been dealing with things up until now. Just this year, the IUCN estimated that more than 40 species of fish may disappear from the Mediterranean in the next few years. The sad truth is that unless governments step up now to protect these and other fishes, the sushi species we know and love will probably disappear before we know it.

Perhaps, as Douglas Adams phrased it in Last Chance To See, we are not truly sadder and wiser after all our experiences - instead we are merely sadder and better informed.

We know that we must change how and what we eat, including making smarter choices when it comes to sushi. The upside is that this is something you - and I - can do. Monterey Bay Aquarium's Seafood Watch has tailored their efforts specifically to sushi-lovers. If you want to really understand why these choices matter, just talk to Casson Trenor, author of Sustainable Sushi: A Guide to Saving the Oceans One Bite at a Time and the website For him, the sustainable sushi comes from a deep love of the food, and his desire to see his children and their children be able to enjoy it like he does.

I couldn't agree more. While sushi is my favorite food, I don't eat it as much as my heart desires. While on occasion I might overindulge (and become a 'tuna slut'), I do know better, and keep my sushi habit in check despite the constant temptation here in Hawaii. My love for sushi is like one of my friend's love for sweets - sure, she could happily eat brownies at every meal, but she doesn't because she knows the consequences. In this case, the science has been unequivocally clear: the consequences of eating sushi with reckless abandon means one thing - oceans without fish.

So there you have it. That's the science of sushi, raw and direct. It's not as pretty a picture as we might like, but it's not hopeless. Hopefully, the fact that you read this post all the way through until this point is a good start. Hopefully, you'll take to heart some of the sobering truths. Hopefully, you'll make ecologically smarter choices when it comes to eating healthy. And hopefully, hopefully, you and I can sit down to a nice plate of nigiri in 50 years and not feel like we're eating the last of my favorite food.