Friday, October 3, 2008

Avoiding isolation... Influencing social norms

In this post we talk about the need to avoid social isolation and help change social norms.

Let's start with some basic questions:

In North America, why are so few people vegan?
And why are there many people who claim to be vegetarian, but actually eat meat?

The answer to both questions has a lot to do with social norms.
The dietary social norm in America is to eat and enjoy meat, milk and other animal-based products. The vast majority of people in wealthy nations follow this same social norm. And even those who identify with another dietary ideal (e.g. being vegetarian), often still follow this same social norm. Why?

Social norms are incredibly powerful.

Science is gradually waking up to this realization. Sure, we've known for ages that children learn by mimicking others. And we're quick to point out that most people follow trends and behaviors blindly "like sheep", victims of fashion and gadget fads. Strangely, we forgot to notice that even "free thinking and independent" adults cave-in to powerful social pressures, which have a measurable impact on our health and well-being.

Nicholas Christakis, a physician-scientist at Harvard Medical School, along with his colleagues has demonstrated this nicely with several recent studies. One study examined the evolution of a large social network over 30 years in the famous Framingham Heart Study - which revealed that obesity actually spreads through a social network the same way that an infectious disease might spread - i.e. through close contacts and friends. The take home here was that the health behaviors that lead to weight gain are in effect contagious. Ultimately, people do what their friends do because they want to be "normal."

((More recently Christakis and colleagues demonstrated that your happiness is actually influenced by the happiness of your friend's friends. (This by the way is one reason I left Boston and moved to San Francisco!) In other words, emotions are contagious.

More on Christakis's work: an Edge interview; NYT article on happiness study; NYT on spread of obesity))

If you really stop to think about it, you will be forced to agree that the way we think is profoundly influenced by others. The vast majority of what we "know" is knowledge told to us by others. Our language is a product of how those around us speak. And so to our actions. More often than not we do what other people do.

So, it's really not surprising that most Japanese eat Japanese food, that Americans eat very similarly to each other, and that Europeans typically gain weight when they move to America. Social norms exert influence on all humans to some degree.

On vegans and social norms:

Vegans are different. It takes a certain kind of person to be able to say "I don't care what most people think or do, I'm going to do what I think is right and best, even if that makes me different and weird in the eyes of society."

Many vegans, at least those who were not raised as such, share this characteristic. I'm not trying to say that all vegans are the same. Far from it. But by nature of the current dietary social norms, to be vegan is to choose to be different.

My concern is that for some (if not many) vegans, being different from the rest of society lends itself to a certain amount of social isolation. This social isolation may have some costs that we should understand and mitigate. Costs that are probably less than the benefits but which may need to be managed.

Even more importantly: learning to minimize social isolation may be the best tool for helping us change the current societal dietary norms.

On eating and social isolation:

Food is central to almost everything we do. Sharing food is incredibly important for social bonding and maintaining relationships (be they business, intimate or plutonic). This is why saying "no" to eating someone's food (say because it's steak and you're vegan) is often interpreted as a personal rejection even when it's rationalized.

Does this mean vegans can't have close non-vegan friends or are destined to be lonely? Of course not. Many of my closest and dearest friends eat meat, and they readily support my vegan-ness in any way they can.

Still, one can't help but feel a little isolated when you're eating with friends at a restaurant and everybody else is merrily sharing chunks of animal flesh, talking about this great steak they ate last week and you are in the corner eating something scrumptious but different, sharing only with yourself.

My point: as a vegan, a certain amount of social isolation is unavoidable if you are living among and with omnivores. We can pretend this isolation is minimal or doesn't exist, or we can explore it and learn how to mitigate it.

The cost of social isolation

Is it possible that the cost of social isolation, even if it's subtle, includes decreased health?

Perhaps. It has always seemed curious to me that studies among vegetarians and vegans who are not shunning the social norm - for instance, among large populations of Seventh Day Adventists (SDA) - demonstrate consistent and marked health benefits compared with SDA's who eat meat and other animal products. Whereas there is more variability in the results of studies that assess vegans or vegetarians who are living mostly among non-vegetarians (generally the results are positive, but not often as robust as we'd expect).

Of course, there are many other reasons why epidemiological studies may not show as large an effect (or even no effect) of a vegan diet compared to non-vegan diets. These reasons include methodological factors (e.g. poor sample size, study design, etc.) but they could also be from unknown confounders. (see definition at end*)

Some of these confounders include poor mental health, shunning of other normal health practices (like going to the doctor, or taking vitamins or medication when prescribed), the inability to self-deceive (this is a fascinating concept, perhaps a topic of a future post, but in short people who can pet their dog with one hand, eat a chicken with the other are good self-deceivers. good self-deceivers do better in business and probably in health as well; i.e. in part it's the ignorance is bliss phenomenon), or other genetic or behavioral factors that may be linked with the personality-type that allows people to shun social norms.

Furthermore, social isolation may have a significant impact on whether someone can maintain a vegan/vegetarian diet. I've met hundreds of people who "used to be" vegetarian/vegan. Why did they return to a meat centered diet? "It was too hard." "I felt better when I started eating meat again." "I missed cheese." etc. Some of these folks were experiencing the side-effects of social isolation and how difficult it is do shun the social norm. (As well as some of the addictive properties of animal-foods, but that's for another post!)

Please keep in mind that this is simply an emerging thesis I am describing; one that I think deserves attention and study, but to my knowledge lacks investigation.

Minimizing isolation, changing the social norms:

Think about the small but meaningful changes we have seen in the last 2 decades. Soymilk - once an obscure drink to North Americans - is now mainstream. When a good restaurant served salad it used to be iceburg lettuce, now it's mixed field greens. Tofu and veggie burgers used to be something to make fun of, now it's a question of preference. In a small crowd, foods like quinoa or tempeh will not be new to everyone. Even the word vegan is relatively mainstream and usually no longer denotes someone from an alien planet.

If you've been paying attention, you'll notice that knowledge of these words has spread throughout society and that enjoyment and preference of "new" vegan foods has spread alongside.

How did this happen? It happened because people like you and me decided that it's normal to eat these foods. We purchased them and essentially financed their existence. Other people did the same. Still other people paid attention (consciously or not) to what we were eating, and decided to take a chance on something new. Knowledge and behaviors spread.

The same phenomenon happens in reverse. Red meat, and especially veal, consumption has slowly but steadily declined over the past few decades in North America. Why? Again, because the idea that red meat is unhealthy, inhumane and environmentally disastrous has slowly spread. In short, because it is becoming less normal to consider red meat good or desirable.

The point is this: everything you do influences people around you, whether you like it or not. If you decide to lock yourself in your home, not patronize restaurants that serve meat and avoid delusional meat-eaters then you lose the opportunity to influence them. You also risk maximizing the downsides of social isolation.

Although I don't know this for sure, my guess is that the more normal, happy, successful and healthy you appear to others, the more they will look to mimic your behaviors, be they lifestyle, political or social behaviors. Yes "radical" people do influence others, but perhaps their main function is to stretch the boundaries of known behavior. If you have 100 body piercings, then suddenly someone with 2-4 piercings seems pretty normal.

As we grow older and evolve, we need to decide what role is the most meaningful and enjoyable for each of us to play. No one can tell you how radical or different from the norm you should be. My only hope is that you consciously weigh the pros and cons, and that the concept of social isolation is something you consider.

To be clear: I don't believe social isolation is a reason not to be vegan. I just think it's something to manage.

Along the way, remember that your actions can help "nudge" people to one day do the same thing. And this can happen without "preaching" or revealing your judgment on their behaviors. The more you understand other people, the more they will understand you.

Granted, there's always a time and place when you have to be vocal about your beliefs and convictions. But it's nice to know they are influencing other people even when you are not trying.

* A confounder is something that could appear to be causing an effect/result/outcome, but is really only linked with the outcome for some other reason. For example, people who buy large size clothes tend to gain weight more than people who buy small size clothes; therefore, a misguided person could say "don't buy large clothes because it will cause you to gain weight". It's easy to see how in this case the shopping habit (buying large clothes) is not the cause of weight gain, but actually the result of it. Buying large clothes is a confounder in this analysis.

Wednesday, September 10, 2008

How can vegans be overweight?

Recently I visited Portland OR, a wonderful city that is especially vegan friendly. I found myself returning again and again to same vegan restaurant/yoga studio a few blocks from my hotel. And every time I went, I was reminded of a question I ponder often:
Why are many progressive, health-conscious, yoga-doing vegans overweight?
Before I offer my answer, let me point out two basic facts. First, on average vegans weigh less than lacto-ovo vegetarians who weigh less (on average) than omnivorous humans. A vegan dietary pattern can protect people from some excess weight gain but it's obvious that many vegans (including raw-foodists) are still overweight. On the other hand, it's fair to presume that these folks are probably a few pounds (if not many) lighter than they would be if they were not vegan.
Second, almost everyone in the US is gaining excess weight. Over two-thirds of US adults are overweight and the entire population weight distribution has shifted drastically over the past 4 decades. This means that even "normal weight" people probably weight 5-10 pounds more than they would had they been born 40 years earlier. Vegans aren't exempt from this phenomenon. We live in a world that makes it easy to eat a lot and hard to expend much energy.
So the main reason why vegans struggle with their weight is the same reason why most people in developed countries are struggling with their weight. (Actually it's a set of reasons which deserve a separate blog or perhaps a book to address)
Let's touch on a few factors that are particularly relevant for vegans:
Vegan Restaurant Portions. If you eat too much healthy food you will gain weight. Vegan restaurants consistently offer mammoth portions. I've eaten at Vegan restaurants in a few dozen cities. One meal typically provides me with enough leftovers for another 1-3 meals. Granted, I am one of those rare cursed folks who has a real hard time eating an enormous volume of food in one sitting. Most people (vegans included) don't have this problem. Think about some of the vegan animals you know (gorillas, elephants, hippos, cows, pigs) and you'll conclude that given ample food any vegan animal can grow enormously large.
Why do vegan restaurants serve so much?! Well, the same reason most restaurants do - economics. Large quantities for little money is considered "good value" by consumers and the cost of the extra portion of food is usually much less than the small additional price increase of the meal. Cheap food means a higher volume of consumers which means more profit. Vegan restaurants often cater to students who are particular sensitive to the value proposition of restaurant meals. And larger portions may broaden the amount of people willing to eat at an all vegan restaurant. Hey Joe Omnivore, want to check out this new vegan restaurant with me? They give you tonnes of food and it doesn't cost much.
Optimistic bias and health halos. Two fun psychological concepts worth understanding. In the context of eating, optimistic bias means you don't think anything bad will happen to you because of your food choices. Other people might gain weight from vegan food, but not me. (This is the same phenomenon that leads most people to think they are not going to die from a heart attack, even when they know that most people do die from heart attacks). We have an intense innate need to feel in control and routinely fool ourselves into believing that is the case. It's hard for us to imagine that a healthy whole foods vegan meal could contribute to weight gain, even in ample quantity.
What's a "health halo"? Here's an example to explain - you see the word "organic" on the front of a cereal box and then throw it in the shopping basket without scrutinizing the nutritional facts or ingredients. The label "vegan" acts as a health halo, magically transforming anything vegan into a healthy food. Vegan smoothie. Healthy! Vegan pizza. Healthy! Vegan donut. Can't be too bad!
In no way am I trying to say you shouldn't be choosing the vegan option. What I'm saying is that all of us are prone to overestimating how good it is for us because it fits a small (albeit valid) list of requirements (no animals killed, organic, etc.). This is particularly true when it comes to calorie content and weight management. We are likely less stringent about portion sizes and calorie monitoring for vegan food then we would be for non-vegan food. And this applies to health conscious vegans too. I do yoga everyday for 2 hours and eat only vegan food. I shouldn't be overweight.
More Options. There are many reasons why a vegan diet causes less weight gain. One simple reason is that it restricts the sheer volume of convenient, readily available calorie heavy food options. At one point this seemed like a bad thing. What do you actually eat? It must be really hard to eat out. My friends used to say this all the time 10 years ago. That's less and less the case, which makes me happy. But in terms of weight management, the more vegan calorie-dense foods available the more vegans will struggle with their weight. Of course, I rejoice at the launch of a new brand of vegan cupcakes, but there is a down side for some.
Basic energy expenditure. We are living in an age of unprecedented calorie-density (e.g. 1200 calorie smoothies) and technological advancement (I have sat unmoving for the past 3 hours only lifting my fingers, but I can honestly claim to be "working"). For most, it's so easy to eat more calories than you use. Adding one hour of exercise a day will make you healthier and happier but it may not fully protect you from weight gain, even on a vegan diet.
A concluding thought.
It is possible for us to create a vegan-friendly world that makes it easier for us all to have a healthy weight. If you are struggling with your weight, adopting a whole-foods vegan diet can be a great step in the right direction. But our work does not stop there.

Sunday, June 15, 2008

Vitamin D Must Knows

As you are reading these sections please keep in mind that the science of measurement and definitions of normal vs. optimal levels for these substances is still evolving. Plus there is incomplete standardization of these tests in the US - meaning the reference normal range may be different from one lab to the other. But these few paragraphs will give you a good background with which to interpret new discoveries and opinions as they emerge!

Vitamin D

The sunshine vitamin. The emerging science of vitamin D is beginning to paint D as a "master vitamin". In short, the effects of vitamin D go way beyond building and maintaining strong bones and normal calcium levels, but may even protect us against certain cancers and help keep our moods bright.

There is little naturally occurring vitamin D in vegan food (although, I have heard that UV exposed mushrooms which then contain vitamin D will soon be on the market), and only a few rare sources of D in animal foods (fatty fish for example). Get this - our skin makes vitamin D (well the precursor to D which is then activated in the liver and kidneys) in response to UV from the sun. Yay for the sun! and skin!
You see the problem. Many of us live where the sun don’t shine. And rates of vitamin D deficiency even in healthy young adults (especially those who live north of the 42th parallel, say in Boston for example, where this blog was written) are alarmingly high - 30% in some series. Vegan and non-vegan alike are at risk for vitamin D deficiency if you avoid or get little sun exposure throughout the year. For instance, it's thought that from November through February, the sun north of the 42th parallel is too weak to stimulate D production.

In the US, dairy milk is always fortified with vitamin D - so this remains the main source for non-vegans, but even this effort has not proven effective at boosting D levels for some northerners. (Granted, rickets (aka osteomalacia in adults) - a consequence of severe vitamin D deficiency - is much more rare than a century ago)

So here's what you should do:
1/ Make sure you have a regular source of D
Your two main options are fortified soy or rice milk plus a daily multivitamin (which will typically have 200 IU of vitamin D), or a vitamin D supplement (which is often coupled with calcium). Cereals and "cliff"/or equivalent granola bars are often fortified as well. Vitamin D is a "fat-soluble" vitamin so it will be better absorbed if taken with some fat containing food.

The exact amount of vitamin D to aim for is a matter of debate. But with the exception of B12 and perhaps a few others, more is not necessarily better and does have potential for harm. In extreme megadoses for example, vitamin D is toxic. Most experts suggest aiming between 400IU and 800IU total per day. That said, some have recently advocated for higher doses (up to 1200 IU) follow the news and your docs advice for updates to these guidelines. The IOM is expected to issue comprehensive revised guidelines mid 2010.

2/ Get your D levels checked once (preferably during the winter), if you live where there is a winter or don't get daily sunshine (you use sunblock or avoid the sun like the plague). The name of the vitamin D we test for in the blood is 25-hydroxyvitamin D.

Just like B12 there is some debate about whether having a low but "normal" level of 25-hydroxyvitamin D is good enough. Typically we say below 20 ng/mL is deficient, below 12 is severely deficient, and 20-30 is low normal. It will take more science for us to know what is "ideal", but based on what is known now I aim to be near 40 or above.

3/ Respect the sun. I detest the word moderation - that meaningless cop out - so I'll say respect. There are probably important benefits of sunshine (vitamin D production being one), but sun burning undoubtedly causes skin cancers, which kill many many people each year. So avoid the summer sun in the mid-day hours when it is strong, but enjoy the early morning and late afternoon rays. Obviously, if you have a high risk for skin cancer this advice does not apply to you - use sunscreen always (and more importantly avoid the strong sun) and get your vitamin D the modern way - through fortified food or vitamins.
Please note - light therapy (aka full spectrum) lights which are wonderful for SAD (seasonal affective disorder, aka the "winter blues") do NOT give off UV rays or stimulate vitamin D production.

Vitamin D Summary - find a daily reliable source - sunshine or a fortified item. This is especially important if you live north of the 42nd latitude (think of a line between northern California and Boston) or if you avoid the sun - and in either case: do get your levels checked one time (preferably in the winter).

Note: since a vitamin D test can cost up to $200, an alternative strategy to testing once is to take a relatively high-dose daily supplement (e.g. 800-2000 IU).

For those seeking a great and thorough medical review on vitamin D search the New England Journal of Medicine for "Vitamin D Deficiency" by Michael Holick : N Engl J Med 2007; 357:266-81.

As always, this blog does not provide individualized medical advice - for that you should find a good doctor.
If any of the above is unclear, please feel free to post related questions.

Site Meter

Monday, May 26, 2008

Moving Beyond Carb Confusion

In this post we talk about the need to refresh our approach to carbohydrate rich foods; and more specifically to reduce intake of "simple" and "refined" carbs.

First, a little perspective.

Carbohydrates are not evil. They have been the backbone of humankind since the dawn of civilization. The large scale cultivation of carbohydrates (e.g. cereal grains) provided the vast amounts of energy (calories) that fueled the growth and eventual urbanization of humans. They have also been important sources of protein, fiber, vitamins, minerals and essential fatty acids.

Throughout our evolution, humans (like all herbivors) have needed sugar and other carbohydrates to survive. Funnily enough, we still do. Of course, the dominance of cereal grains as the provider of carbohydrates is a relatively new phenomenon (10-15 thousand years). And the advent and supremely high intake of refined carbohydrates is extremely recent (within the last 50 to 100 years).

With all the media attention carbs have gotten recently, you would think our grain intake had reached historics highs. Actually, we eating less grains then we did 100 years ago.

Per Capita Grain Consumption.
Source: Putnam & Allshouse. U.S. Per Capita Food Supply Trends. Food Review. Sept. 1998

So why all the bad press? The reason is that our intake of refined grains has indeed skyrocketed: see the recent upslope in the graph above (a 50% increase in grain intake since 1973), the vast majority of that increase is from refined grains.

And study after study continues to point a damming finger at people who eat the most refined grains - revealing they have higher rates of obesity, heart disease, diabetes and so on.

What is refined or processed?
Most grains come from grasses. Each stalk of grass yields numerous berries or seeds -these are the nutrient and energy dense bundles that can generate entire new grasses. Fortunately for us, they are also edible.

To a certain degree all grains require some "processing" - harvesting, removing the outer husks from the grainseed and then sprouting or cooking. Yes, some grains like corn can be eaten raw. But most become more digestible and valuable when soaked, sprouted or cooked.

However, when we talk about "refining" we're talking about processing the grain even further by removing the outer layers (the bran + germ) from the grainseeds.

Layers of a whole grain.
Image Source:

Grains, either in whole or refined form, can also be crushed or milled into flour or ground into meal. However, refined grain flour has been stripped of so many nutrients that they sometimes add back a small handful of the vitamins and minerals lost to the end product, called enriched flour. (Depending on the grain, processing it into a flour or meal also further strips it of some protein, fiber and nutrients.)

What is wrong with refining and processing grains?

Well, as mentioned, it turns out that most of the valuable nutrients, fats, and fiber are in the outer parts of the grain. Refining leaves us mostly with starch (long chains of sugar), a bit of protein and a few nutrients - we call this package a refined carbohydrate. So if you eat only refined and processed grains then you're missing out on most of the beneficial properties of the whole grain.

In the absence of fiber, these refined "carbohydrates" are rapidly absorbed from your digestive system - giving you a blood sugar spike. Eating refined grains raises your risk for diabetes; eating more whole grains lowers it.

Because fiber is (by definition) not absorbed, fiber-free grain (i.e. refined grains) is also more energy-dense. You'll eat more calories of a bowl of white rice then you will brown rice. Eating more refined grain will make you heavier; eating more whole grain will help you stay leaner.

A brief tangent. What's the difference between simple sugar and refined carbohydrate?
Sugar can be called simple or complex depending on how it's packaged. One or two sugar molecules by themselves = simple sugar (e.g. table sugar). Many sugar molecules chained together = complex sugar (e.g. starch inside grains or potatoes). For reasons you might guess, it's not too useful to talk about simple vs. omplex sugars because complex sugars by themselves are easily broken down into simple sugars. What matters is the whether the sugar is packed in fiber and nutrients - i.e. is it refined or unrefined?

Finally, refining grains into sugar makes them more addictive. This may be true of both simple (e.g. high fructose corn syrup) and to a slightly lesser degree complex sugars (e.g white wheat flour) refined from grains. This is a controversial point, but the emerging evidence is pointing in this direction. Sugar acts on the brain in a manner similar to many drugs. And refining makes all drugs more addictive, for at least two basic reasons. First, the active ingredient is vastly more concentrated and second it gets to the brain quicker, setting up a stronger cycle of high-withdrawal-high. Think: cocaine vs whole coca leaf tea; intravenous morphine vs. opium poppy milk.

Of course, we can take this comparison too far, but it is certainly possible that the addictive properties of sugar explain why so many of us have a hard time 'moderating' our intake of refined grains.

But you said sugar wasn't evil.

It's not. We all need sugar. But too much is bad. And slow-release sugar (i.e. sugar coupled with fiber and healthy fat) is arguably much better for us.

Refined grains are everywhere.
Cereal. Pasta. Bagels. Muffins. Rice. Crackers. Candies. Soda. Cakes. Pastries. Bread. The majority of these foods are made with refined grains today. Take a close look around and you will see how dominant refined grains are in the food supply.

Most of us are eating several of these foods everyday. They fill us up, preventing us from eating more nutrient dense foods. And as everyone knows, it's very easy to eat too many of them.

How to spot refined grains:

Refined grains are now the norm, so you will never see the word "refined" or "processed" in the ingredient list. Instead you need to recognize all the terms that code for refined:
-flour (or enriched flour)
-rice (or rice syrup)
-corn syrup (or high-fructose corn syrup, aka HFCS)
-corn or rice starch
....And so on.

Another route is to realize that if the grain is still in its whole form then it will be labeled as such: the words "whole" or "unrefined" will be put in front of the grain name. e.g. whole wheat.

There are a few exceptions to know about: corn and oats are always "whole" grain. But they can be processed to one degree or another. Oat groats are much less processed than the steamed and squashed "instant oats", and therefore better for you. Whole grain rice will usually be called "brown rice" or "whole grain brown rice".

How to eat more whole grains:
1/ Start with your staples:
start by looking at the foods you eat almost everyday. For example, many people eat a grain based breakfast (e.g. cereal, toast, muffins). Making sure these breakfast staples are 100% whole grain is a great start.

Likewise, many people eat rice or pasta almost every day. Switch to brown rice (I suggest investing in a rice maker). Experiment with the large variety of whole grain pastas (brown rice, quinoa, spelt, whole wheat) - some taste better than others, so keep on trying different ones until you know which you like best.

2/ Give yourself a few weeks to acquire the taste and habit. For example, some people love brown rice the instant they eat it, but for others it takes 3-4 weeks (or more) of frequent attempts before it starts tasting good. But in time, most people come to prefer brown to white rice.

3/ Create demand. We are creatures of habit and convenience. Ask for whole grains at restaurants and stores and soon enough you will start seeing them everywhere. We're already seeing this happen...

How to eat less refined and processed grains:

The first step is to switch your staple foods to whole grain varieties, as above.

Beyond that you will probably need to cut back on foods you probably shouldn't be eating on a daily basis - cookies, pastries, cakes, muffins, crackers, pancakes, waffles, crepes. These are treats, not everyday foods.

Yes, you can and should look for whole grain varieties of these foods. But chances are you will find varieties that might have some (but not all) whole grains in them. For instance, let's talk about cake:

Cake, even if made with whole wheat flour, is going to have a good amount of sugar (essentially the equivalent of maximally refined and processed grains) - otherwise it's just not a cake!
Sugar comes in many forms - honey, agave, concentrated fruit juice or jam, brown rice syrup, brown sugar, molasses, cane sugar, beet sugar, high fructose corn syrup, maple syrup. Yes, some of these are slightly "better" forms of sugar than others, but they are still sugar - a touch is good, a lot is not.
In summary, whole wheat vegan double chocolate cake is a fantastic creation when made well. It should be thoroughly enjoyed, but not everyday.

Sunday, February 17, 2008

Vegan Omega 3's and more

A Brief Overview of Fats
(If you know your fats well, skip to the end for the bit on Omega-3s)

Fat, also called lipid (and sometimes referred to by its liquid name "oil"), really describes a large and diverse group of substances that share a similar chemical structure of carbons linked together. Because of this similar structure, fats all are packed with energy, making them excellent storehouses for energy in the body. Fats are also a critical part of every single cell in our body and serve innumerable functions beyond that of simply providing energy.

There are groups of specialized fat storage cells called "adipose tissue" (when people talk about someone's fat, or love handles, or junk in the trunk, etc. they are talking about adipose!). A recent explosion in scientific research has begun to uncover Adipose tissue's hundreds of novel functions -- scientists are so impressed that they are calling for Adipose to be classified as a separate organ system.

Did I say I was going to be brief? Ok, so let's talk about fats from a vegan perspective according to the way we classify and organize fats:

Saturated Fats - saturated refers to the fact that all the carbons in these fats are full (i.e. saturated) with hydrogens. That's why I'll include partially hydrogenated and hydrogenated vegetable oils in this category. These fats are still a grouping of many types of fats, some of which are worse than others, but in general, these are the guys that raise blood cholesterol and contribute to heart disease and a very large host of atherosclerotic diseases. Yes, most saturated fat in the American diet comes from dairy and other animal foods.

But hefty amounts of saturated fat can creep their way into the vegan diet in the form of margarines, baked and processed foods (which contain hydrogenated vegetable oils, or palm oil, cocoa butter and coconut oil) and a few whole foods like avocado, chocolate, Brazil nuts or coconut.

Are all of these foods bad for us? No. For example, dark chocolate contains ample saturated oils but many studies point to the net benefit of daily intake of a small amount of dark chocolate. Similarly avocados are not enemy number one in health circuits and contain beneficial fat soluble vitamins and nutrients.

The biggest question of debate is palm oil (now gaining infamy for its role in rain forest destruction). Palm oil is ~50% saturated fat and Palm Kernal oil is ~88% saturated fat. Palm oil can be further hydrogenated or fractionated to get a more saturated fat rich product. It seems clear that hydrogenated palm, partially-hydrogenated palm and palm kernal oil are plain terrible for you and your heart. Avoid these in any quantity. So the question is about raw or unrefined palm oil, which is touted to have lots of beta-carotene, vitamin E and other antioxidants. Here studies show mixed results - some reporting a beneficial effect on blood lipids (cholesterol, etc.) and other showing detrimental effect. The differences may have to do with who was selected for the study (e.g. it may have a worse effect on men and people predisposed to bad lipids), on the type of palm oil (red palm may be better than regular palm), how "crude" or unrefined the oil is (in the same way that unfiltered extra-virgin olive oil is far superior to "light" olive oil), or on other factors that are not clear to me. Part of the argument for palm oil not being bad is that the saturated fat is mostly in the 2nd position of the 3 fatty acids on the glycerin backbone - and that this is much less bioavailable (i.e. digested/absorbed) and that palm also contains beneficial mono and polyunsaturated fats.

So in sum, my sense is the verdict is still out on unrefined palm oil. I'll chose to keep my intake small until more is known.

Trans Fats - Most often these are the news-savvy by-product of hydrogenating and modifying oils and contain a chemical structure not often found in things we eat. Until recently, about 80% of trans-fat in the US diet came from hydrogenated soy oil. There is now plenty of science revealing how toxic these critters are... thus the ban on trans-fats now in place in several cities. Do not buy anything with trans fat and be aware of products that say "now trans-fat free" - check to see if they've replaced their trans fat with palm kernal oil or other not-so-good oils.

Unsaturated Fats - we typically divide these into mono-unsaturated oils (think: olive oil, mmm) and poly-unsaturated oils (think: most vegetable-based oils). I won't talk much about mono-unsaturates, except to say they seem to be good for us.

Polyunsaturates can be further divided into
categories based on their chemical structure (for you chemistry lovers: the position of the first double bond in the carbon chain), the main groups being Omega 3, Omega 6 and Omega 9.

Omega 3 and Omega 6 are the "essential fatty acids" because if you don't eat any you'll die! You'd be guessing right if you thought that both have beneficial properties. But omega-6s are in so many foods you eat that you don't have to worry about getting enough. Omega-3s are much harder to find and there is growing recognition of the theory that the balance of Omega 3's to Omega 6's in the diet is important. And that our ratio is wayyyy out of whack - we eat way way more omega 6's than 3's (roughly 10x more, rather than the 2-4x more that may be 'ideal').

Where are the Omega-3's hiding?

Well there are modest amounts in some common vegan foods, most notably tofu and other regular fat soy products (excluding soy-oil). So all of us do eat some omega 3's. But given the abundance of Omega 6's in our diet, a strong argument can be made for getting more of the 3's.

Papa Omega 3 and the important fine print of omega 3s:

The parent of the omega 3 family is a fat called alpha-linolenic acid (LNA). The main vegan sources of omega 3 (such as flax oil, canola oil, tofu, walnuts) are mostly alpha-linolenic acid. From LNA our bodies can make some other omega-3s special kiddies called EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid).
EPA and DHA are the omega 3's most well studied that lower the risk of dying from heart disease. It's thought that large amounts of omega 6 can suppress our ability to convert LNA to DHA and EPA, which may be a particular disadvantage to the common vegan diet at present. So the major question still unanswered is can we make enough EPA and DHA by eating predominantly LNA? And if not, how much does this matter?

I'll skirt these questions by saying this: My hunch is that the modern vegan will get meaningful benefits from improving fat intake - through the combination of reducing harmful fats, increasing omega 3s (especially by replacing omega 6 dominant oils with omega 3s) and likely added benefit from supplementing with DHA (vegan EPA can be extracted from some plant seeds but is still hard to come by right now, and our bodies likely find it easy to convert DHA to the main issue is getting or making enough DHA).

Who should pay particular attention to omega 3's?

Those at risk for heart disease and stroke (ok that's most of us); those with depression and women during their childbearing-potential years, especially if you are pregnant or breast-feeding (omega-3s are critical for normal development of the brain).

How to get your omega 3s & improve your balance of 3 to 6:

1. have a daily source of concentrated omega 3s, e.g. 1-3 tablespoons of Flax oil. Flax meal (ground flax seeds) is also an excellent choice because you get the other benefits of the seed, but obviously you need to eat more to get the same amount of omega-3s in the oil. NOTE: whole flax seeds will pass straight through you so are not a viable source (watch out for this in products that claim to have omega-3s from flax).

for cooking and baking - switch from generic vegetable oils to canola or extra-virgin olive oil. Do not use shortening or margarine at all. Experiment with flax meal+water as an egg replacer in baking. Pay close attention to the ingredients in those vegan baked goods we love so much.

3. for spreads - again throw out the typical margarine. Use an oil like olive, canola or flax. Or look for specialty margarine-like spreads that boast omega 3s, or at least no hydrogenated, partially hydrogenated oils or palm kernal oils (and thus don't have trans fat or excess saturated fat).

4. Consider a daily source of vegan DHA. These are typically made from algae (precisely where the fishees get theirs) and come in supplement form (e.g. Omega Zen, Health from the Sea and Neuromins (if you don't mind gelatin)) and are now being added to some soymilks (e.g. Silk special formula).

5. Read your labels. Most of us eat an extraordinary amount of packaged and processed foods - try to minimize the junk - stuff with refined grains, hefty sugar helpings and bad oils...

6. Look for fun foods - e.g. refrigerated dark chocolate truffles made with omega-3 rich oil.

7. Focus on the minor sources too. There are plenty of vegan foods that have small amounts of omega-3 (like leafy greens) and or decent amounts but we don't eat them often (like walnuts, hemp and pumpkin seeds). Of course, there are lots of other good reasons to eat these foods too. A recent study on walnuts suggest that daily intake of ~2 ounces offers the same cardiovascular protection as fish.

8. Keep your eye open for more plant based EPA and DHA. These compounds are being discovered in a decent handful of plants (often in the seeds of plants we don't commonly eat) and are sure to make their way to us in functional foods or supplements in the near future...

Site Meter