The Paleo Diet is Rational

The paleo diet is one of the latest fads to hit the world of dieting. It is supposedly based on eating only foods that our ancestors in Paleolithic times, some 12,000 years ago, supposedly would have eaten. Thus, the diet permits meat, fish, fruit, most vegetables, nuts, and plant-based oils (such as olive and avocado) while excluding dairy, grains, cereals, legumes (beans, peanuts), processed oils, processed sugar, alcohol, and coffee. The idea behind the diet is the claim that our bodies had, by the end of the Paleolithic, evolved to survive on the foods available at the time and are not designed to process foods that were introduced since then. There are many fatal flaws in this whole idea.

The most serious flaw is the assumption that evolution “designed” us to be an ideal match for our environment and diet 12,000 years ago. This is completely wrong, as any high school biology student should be able to tell you. Evolution doesn’t “design” anything, all it does is favor the continuation of genes that are associated with leaving more offspring. Thus, a caveman who was sickly and died at 25, but left 12 children, was an evolutionary success and his genes would continue in the population. In contrast, another caveman who lived a healthy life to the age of 60, but left only 1 or 2 children, was not a success in evolutionary terms. In other words, the notion that Paleolithic folks were ideally adapted to their diet is pure nonsense. As long as their diet allowed them to leave children, that was enough.

A second serious flaw is the diet’s assumptions about what foods people did and did not eat back then. There is, for example, quite a bit of evidence that Paleolithic humans ate grains and legumes, but these foods are forbidden by the diet. In fact, there is evidence that humans were cooking and eating tubers and other starchy vegetables as much as 300,000 years ago. Paleo humans did not eat peppers, tomatoes, avocados, potatoes, pineapple, or blueberries (among others) because these are new world plants that were not available during Paleolithic evolution. Yet the diet allows them all. Dietary flexibility was a hallmark of humans and one reason for our evolutionary success—we did not evolve to eat certain specific foods, we evolved to eat pretty much anything. Would anyone care to argue that Paleolithic humans in the sub-arctic zones, the rain forest, the plains, and the tropical coastal regions ate the same or even similar diets? I don’t think so.

A third flaw is the claim by diet proponents that human genetics have not changed in any meaningful way since Paleolithic times and therefore the human digestive and metabolic systems cannot have adapted to deal with “new” foods. This is flat-out false. It is well documented that human genes have changed in response to the introduction of dairy into the diet and to the development of agriculture, with the greater availability of wheat and other grains. While on the subject of genetics, it’s impossible to understand why humans have multiple copies of the gene for amylase, an enzyme whose sole purpose is digesting starches, if starchy foods had not been an important part of the human diet for a long time.

That’s strike three, I believe!

As if we needed a strike four, the life expectancy of humans in Paleolithic times was somewhere in the mid-30s. Is theirs the diet you want to eat? Of course, many other factors have contributed to the increase in life expectancy, including improvements in medicine, public health, and nutrition. Oh wait, did I say nutrition? You know, like eating grains, legumes, and dairy?

There are good aspects to the paleo diet, namely the avoidance of overly processed foods and of excess carbs and sugar (emphasis on excess). But, there’s nothing “paleo” about these ideas, they are part of many dietary regimes. So if you want yet another trendy fad diet to waste your time and money on, be my guest and go paleo.

A pressure gauge on your propane tank is useful

Many folks have paid for a pressure gauge on their propane tanks in the mistaken belief that it tells you how much propane is left. Me too, I got one before I figured out that it is useless. How come? High school physics class to the rescue!

In the tank, the propane is mostly liquid. At the top of the tank, above the liquid propane, is gaseous propane. When you open the valve, some of the propane gas is released, and some of the liquid vaporizes to maintain what physicists call the vapor pressure – the pressure at which liquid and gaseous propane are in equilibrium. As long as there is some liquid propane in the tank, this pressure remains the same (although it does vary with temperature, being higher when the temperature is warmer). Whether 95% full or 5% full, the pressure is the same. Only when there is no more liquid propane in the tank will the pressure shown on your gauge drop. You can tell how much propane is left by weighing the tank, but that’s a bother. You can also tell by feeling the side of the tank when it is in use (when your grill is on). At some place the tank will be colder below, warmer above. That’s the level of the liquid propane. Bottom line? Keep an extra tank on hand.

Vegetarians can eat Seafood

I have met more than one person who claims to be a vegetarian, but happily chows down on fish, scallops, and other seafood. Sorry, this just won’t wash. Fish are animals, and by definition a vegetarian does not eat animals. No, Virginia, a clam is not a vegetable!

Of course there is nothing wrong with eating seafood, it is tasty and healthy. But, it is not vegetarian. If you eat seafood but no other animals, then you are a piscaterian.

Quinoa is a grain

Well, it sure looks like a grain and is usually used like a grain, so what’s up? Fact is, quinoa is the seed of a plant in the goosefoot family, which is not a grass—and grains like wheat, rye, and corn are the seeds of grasses. Of course this technicality does not change the fact that it is tasty and nutritious, but it might be useful in a game of trivia!

Sharp knives make cutting your fingers more likely

A sharp knife cuts more easily, so this make sense – right? But, it is not true. With a sharp knife, cutting is easily done and nothing needs to be forced. And it’s the forcing that causes cuts, when you have to press down hard and the knife slips onto your finger. Ouch! With a really sharp knife, your cutting can be smooth and relaxed, with less danger of cuts. So, keep your knives sharp!

Roasting coffee at home is difficult and not worth the effort

To the contrary! Since being turned on to coffee roasting a while back (after a visit to an organic coffee plantation in Nicaragua), I regret not having started sooner. If you want better, cheaper coffee for little effort, read on. If you like Charbucks – err, I mean Starbucks – coffee, don’t bother.

  • Process: A coffee roaster can cost as little as $130. It looks sort of like a blender and works by blowing hot air up through the beans to agitate and roast them. Add the green (raw) beans, turn on, and forget – it’s that simple. You can vary the type of roast (light, medium, dark) by varying the roasting time and/or temperature. This process will generate some smoke, particularly when making a dark roast, so be forewarned. There are also drum smokers that heat the beans in a rotating drum.
  • Savings: Green coffee beans, easily available over the internet, cost in the $5-7 / pound range with a few exceptions for super-premium beans like Jamaica Blue Mountain. Beans lose 15-20% of their weight in roasting, so a pound of roasted beans ends up costing $7.00-$7.50 / pound. Compare that with the $12-15 that high quality roasted beans cost. Your savings will soon pay for the roaster and you’ll be saving money.
  • Variety: My favorite source of beans, Burman Coffee Traders, currently lists green beans from Costa Rica, Hawaii, India, Brazil, Colombia, Ethiopia, Guatemala, Indonesia, Jamaica, New Guinea, Tanzania … the list goes on. Decaf beans are available as well. Plus, you can experiments with your own blends.

So, if you love coffee – good coffee that is – you might want to try roasting your own.

Slamming the oven door can ruin a soufflé

A soufflé is a delicate creation that rises due to expanding bubbles in beaten egg whites. A sudden shock such as the oven door slamming will, supposedly, cause it to collapse. While this may be a nice plot twist, tests show that it isn’t true – your soufflé will survive a slammed door just fine, as will delicate cakes.

Acidic marinades make meat tender

Many people believe than an acidic marinade – one containing wine, vinegar, or citrus juice – will make meat tender. In fact, the opposite is often the case. Acid interacts with the proteins in the meat, causing the protein molecules to pack more closely together and thus squeezing liquid out of the meat. The result? Tough and dry steak, chicken, or what have you. What’s more, extended exposure to acid can cause the surface of the meat to become mushy because the proteins start to break down. The rule, then, would be to keep acidic marinade periods short, but then of course the flavor won’t get into the meat very well. My approach is to rely on non-acidic marinades.

The fact is, marinades in general don’t have nearly the effect that many people think because the flavors just cannot penetrate beyond a millimeter or two at the surface. Salt and water in a marinade can penetrate deeper, and the benefit of most marinades is the result this factor.

Coffee labelled “fair trade” is the highest quality

The Fair Trade Labeling Organization was started in response to the plight of coffee growers, who often received dismally low prices for their product. If a coffee cooperative met certain labor, environmental, and social standards (among other things), their coffee could carry the Fair Trade label, and they received a higher per-pound price than they would otherwise (still a low price, but definitely an improvement). Fair trade coffee is a small part of the total coffee market, about 1/2 of 1%, but it allows socially conscious consumers to ensure that the growers of their coffee are receiving a fair shake – this is a good thing!

Unfortunately, many people have the misconception that any coffee labeled Fair Trade is automatically of the highest quality. This is not the case. It’s an open secret among high-end coffee roasters and drinkers that Fair Trade coffee is often of lower quality. After all, the requirements for earning the Fair Trade label have nothing to do with the quality of a grower’s coffee, but only with meeting the Fair Trade requirements. When the price a grower receives for coffee has little or nothing to do with quality, there is no incentive to work to maintain or improve quality – with predictable results.

I am all for the Fair Trade idea, I have traveled in Central America and am aware of how much work goes into growing and harvesting coffee, and these people should definitely be paid fairly. The fact is, however, that if you are fussy about the taste of your coffee, as I am, and seek out only the highest quality beans, the growers of those best quality beans will have received more than the Fair Trade price for their crop.

There is a new coffee certification called Direct Trade that was created in response to problems with Fair Trade. It too requires reasonable prices paid to the growers, but also provides incentives for high quality coffee. You don’t hear much about Direct Trade, but you can learn more on Wikipedia.

So, if you like the taste of the Fair Trade coffee that you buy, that’s great, but if you really want to help the growers, insist on the highest quality coffee you can find, or buy Direct Trade. Hint: it’s not at Starbucks.

A pinhole in a raw egg will prevent cracking while boiling

This myth is based on the reasonable idea that eggs crack, when being hard- or soft-boiled, because the air in the shell expands from the heat. The pinhole is supposed to release this pressure. Reasonable, yes, but tests show that a pinhole really does not reduce cracking. Rather, cracks occur either because the egg already has an invisible crack in the shell, which expands during cooking, or because the egg is being knocked about in the pan by too-active boiling.