The Happy Diet!

Some cause happiness wherever they go; others whenever they go.
—Oscar Wilde.

The Scream

The Scream by Edvard Munch: in need of yogurt?

I’m grumpy, as usual, because daylight is so damned bright. Worse yet I’m at work, which really buzz-kills my day. If it weren’t for work, I could be doing something amazing and exciting, like watching Survivor reruns while crunching down Cheetos and chugging beer. Yeah, I know what you’re thinking: That’s what I want too! Yet, instead we plod off to work with a bunch of other depressed people whom we call our coworkers and stare at the poster of The Scream we have tacked to our cubicle wall.  Like millions of Americans, I’m depressed. And just a little anxious.

So when I came across some research that said eating certain foods could make you happier, I thought I would look into it. Okay, my wife insisted.

What I found was wild: Just when you think you might have a little free will after all, comes more proof that “you” are a vanishingly small satchel of hope that is being squashed flat under the boot of modern science.

In this particular study, scientists watched with hand-wringing glee as they fed mind-controlling bacteria to their hapless subjects. What insidious method did these Voodoo scientists use to inoculate these poor people? The bastards used yogurt!

That’s right, after eating yogurt for a month, the subjects were happier. Well, that’s just great. But how can you expect anyone to eat yogurt like that? I hate yogurt with all its smarmy, fruity unctuousness. The more I thought about it, the more I realized that this diet – at least for me – would be pretty humiliating. So I jumped on it.

Put Your Bacteria on the Happy Diet

The theory behind the Happy Diet is that bacteria can actually communicate with your brain through nerves, hormones and the lymphatic system. It’s called the gut-brain axis — an authoritative name for a dimly understood partnership. There is still a healthy debate about exactly how your gut talks to your brain and vice versa. Some of it, however, seems pretty settled: there is a second “brain” in your body, and it’s not Steve Martin.

The Man with Two Brains

Maybe The Man with Two Brains isn’t so weird after all.

It is called the enteric nervous system (ENS) and it’s big, covering your entire intestinal tract. From pie hole to poop chute, the ENS picks up information about what’s going on inside your gut and then sends signals to the muscles lining your GI tract. When something like food poisoning happens to you, it’s your ENS that gives the order to churn out massive quantities of fluid to flush everything out of your gut, from both ends, if necessary.

The ENS is wired to your brain via the vagus nerve, and this part seems pretty straightforward, at least as far as anything to do with neural circuits can be straightforward. In animal studies where nasty bacteria were used to induce anxiety, severing the vagus nerve stopped the anxious behavior. However, a complete understanding of the neural details remains elusive.

At least some of the basics can be roughly sketched out: a bacterially diverse gut is a healthy gut, and a healthy gut can make you happier. When you get some kind of microbe oligarchy where one bacterial family starts to dominate, you may be attacked from within: your gut barrier may be breached, your immune system then goes on alert and you become inflamed. That can spoil your day, even if you don’t recognize that the problem started in your gut. So maybe I’m not really grumpy. Maybe I just have cantankerous bacteria.

A Cast of Billions

There are four bacterial players that deserve top billing: lactobacillus, bifidobacteria, streptococcus and clostridia. You may recognize lactobacillus as the living part of yogurt. Bifidobacteria are also fond of yogurt and fiber. In this story, clostridia and streptococcus are the bad guys. When you feed the good guys with something like fiber or complex sugars like lactose (from milk), they multiply like crazy and push aside the nasty clostridia.  When you neglect the good guys, clostridia and other aggressive microbes take advantage of the chance to switch into Animal House mode.

We usually think of fiber as something like tree bark, and indeed tree bark is fibrous. But for all its tough-guy image, fiber simply consists of sugar molecules strung together in a chain that our humble human guts can’t process. Bacteria, which mammals welcomed into their wet spots some millions of years ago, just love fiber. They have no problem chowing down on these sugar chains, and when they do, they poop fatty acids – ambrosia for the cells lining your gut. This is a sterling example of symbiosis at its best; it signifies a long and fruitful partnership.

Dancing bacteria on the Happy Diet

But some of these bacteria are better for us than others, at least in the proper measure. The good guys feed you; the bad guys feed on you and may accidentally kill you. I say accidentally, because most of them really don’t want to kill you: they have a vested interest in getting you to feed them. When your gut feels good, that means your good bacteria are performing their most impressive job: protecting you from the bad bacteria. It’s a continuous battle, and these microscopic warriors are on the front lines.

Lactobacillus and bifidobacteria excrete a fatty acid compound called butyrate, which turns out to be a superfood for the cells that line your gut. In effect, these good bacteria feed and repair your gut, helping to address Crohns, IBS, ulcerative colitis and a host of other nasty problems all related to a leaky gut. And, it turns out, those maladies can also make you anxious and depressed. That might seem obvious, but the brain often receives some pretty hazy messages from the gut, like the feeling of butterflies or hot coals. Sometimes the feelings are so vague that it’s hard to know where they’re coming from at all. You simply feel anxious.

Messages of danger (or health) are transmitted in multiple ways. One is by way of the vagus nerve to your hypothalamus, a part of your brain that triggers hormones that can affect your appetite, mood and the movement of your gut. This is a fast communication link taking a fraction of a second, perfect for reacting quickly to poisons or bacterial toxins.

A slower, steadier communications channel uses cells of the immune system. For instance, leaky guts let bad bacteria through, which triggers an immune response. These inflammatory signals travel through your lymphatic system as well as your blood, affecting other parts of the brain/gut axis, again affecting your mood.

Long-term or short-term, the brain-gut axis contributes to our levels of anxiety and depression, and we ignore it at our peril.

So what to do?

The Happy Diet attempts to address this issue with “happy bacteria”. The first thing I had to do was ditch the fruity yogurt. Besides being unmanly (heaven knows I’m a lot of man), these yogurts have so much sugar they may have you bouncing off the walls and my walls just aren’t that sturdy. I found, instead, that thick Greek yogurt was basically the same as sour cream, and since manly men use sour cream on their manly baked potatoes, I felt safe. Plus, if god had meant us to eat fruits, they would grow on trees, not hide at the bottom of a yogurt cup.

So I started to eat Greek yogurt on everything. The idea here is to get the live bacteria, so you can’t actually cook with it. But you can add it on top of soups (yes!) or on top of other cooked veggies. Try it on scrambled eggs. Depending on your levels of gustatory fortitude, you could try it in your cereal, but I found that pretty disgusting, all the way to the bottom of the bowl.

And I found another source of lactobacillus that really blew up my skirt (my manly skirt): homemade fermented pickles! The making of pickles deserves an article on its own, because it is so surprising and so delicious. For instance, do you know the recipe for sauerkraut? It’s cabbage and salt. Yup! Slice some cabbage, salt it, and within minutes it starts to make its own juices. Lactobacillus is everywhere, and enough is on the cabbage to start a huge microbe party. Stick it in a room-temp crock pot, making sure it stays submerged under the juice (lactobacillus doesn’t like oxygen), and in a week you have the best kraut you’ve ever tasted. You can do the same with pretty much any veggie, turning a humble cauliflower, for instance, into a sublime snack.

These are not your ordinary pickles. Unlike vinegar pickles, which use acetic acid to do the job, these are primarily pickled by lactic acid. The taste is different, but awesome. If you take up pickling, I hope you remember where you heard about it, and send me some recipes. Sandor Katz is the czar of pickledom, and I simply can’t improve on his wonderful site Wild Fermentation. Check it out – it could change your life!

A few caveats are called for here. Getting bacteria past the acids of the stomach and the enzymes in the small intestines isn’t easy. And assuming some bacteria make it past that gauntlet, they still have to fight their way into a well-fortified colon. Not everyone gives that a winning chance. But including mess kits with this bacterial army, in the form of prebiotics like lactose, may help things along. Combining pre- and probiotics together is called synbiotics, and it is the basis of some new attempts to re-engineer your gut bacteria.

Keep in mind that your particular bacterial zoo gets well established early in your life and is difficult to dislodge. Although studies have shown that you can change the ratios of your gut bugs in less than 24 hours, the effect is transient. As soon as you start eating the same old food, your gut snaps back just as quickly. You may be able to make changes with a new diet, but once you start, you might have to keep it up forever.

A final caveat is that not all scientists agree that fiber is good for you. A group out of Stanford thinks that fiber can be bad for people, especially people with IBS. There is evidence on both sides, which makes this a scientific throw-down that should be fun to follow. Right now, I give the edge to fiber, which is natural and has been a key part of our diet for millennia, whereas the Stanford plan is a very restrictive elimination diet. Nevertheless, be aware that the final word has yet to be written on this topic.

The Happy Bottom Line

So did it make me happier? Well, that is pretty darn subjective. I made up my own checklist to track my changes. Overall, I came out somewhat happier at the end of the month. The day no longer seems so irritatingly bright. My coworkers seem less standoffish. But the best part is that my stomach seems more contented. Still, this is totally anecdotal, so don’t take my word for it. Try it yourself. And if you’re not a manly man, don’t fret: The original yogurt study was done with women, and the results were significant. There are tons of sources of fiber you can try, but just don’t go too sweet. In this story, the only good sugars are the ones that are chained up.

I can tell you one thing: unlike most of the humiliating diets I discuss at this site, which I can’t wait to terminate, I’ve now incorporated yogurt and fermented pickles into my life. And I don’t think I’ll ever go back.


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