When a hairdresser is nearly finished cutting long hair, she (or he) will look to see if both sides appear consistent. If she doesn’t do that, one side may end up longer than the other. (I know, because I’ve had that happen.) What if the hairdresser doesn’t take this step? I don’t know about you, but I wouldn’t go back.

Some scientists are performing equally sloppy science, and by so doing are easily able to “prove” that things like the keto diet shows no long-term adverse effects.

The exact words from one such study’s discussion section, published in Experimental and Clinical Cardiology, were, “In the present study, a control population on a low fat diet was not included due to the difficulties in recruiting subjects for a control group.”

That’s the scientific equivalent of not making sure both sides of the haircut are even. It means the authors, Hussein Dahsti and Mathew Thazhumpal et al, found it too difficult to find people who were willing to eat a high-carbohydrate diet, yet they went on to say there are “several studies” where other researchers did compare “the effect of a low fat diet with a low carbohydrate ketogenic diet.”

In other words, other researchers didn’t seem to have the same struggle to find people willing to eat a high-carbohydrate diet.

It’s very hard to trust the conclusions of researchers who are unwilling to go to the effort to create a randomized study with a control group, even though other researchers have shown it’s not that difficult. You don’t even have to be a scientist to find people in the United States willing to eat a low-fat diet.

Another obvious cause for concern is that Dashti’s study is titled “Long-term effects of a ketogenic diet in obese patient” implying they think six months is long-term. But at least one of the two other research groups referenced noted that six months is a “short duration” study. Long-term usually means years or decades, not months.

I mentioned that fact with one keto supporter and his comment back to me was, “Read about Paleo, it was a very long era.” I suppose he was implying that our ancestors ate that way in the paleolithic era and therefore it’s healthiest (ergo, no research study needed). However, Michael Greger, M.D., founder of NutritionFacts.org, thoroughly addressed why that thinking is false, in a series he called, “The problem with the Paleo diet argument.”

He said, “Though it may be reasonable to assume our nutritional requirements were established in the prehistoric past, the question of which prehistoric past remains.” He goes on to talk about evolution and what we ate. While I take a different perspective from his evolutionary stance, I agree with his conclusion is that we have eaten “over 95 percent plants” over all of these years.

His pro-natural-selection argument is, if our bodies were designed to eat meat and “a lifetime of eating like that clogs up nearly everyone’s arteries, why didn’t the genes of those who got heart attacks die off and get replaced by those who could live to a ripe old age with clean arteries, regardless what they ate?”

It is those who eat mostly plants, such as populations in China and Africa who are nearly free of chronic disease in old age. He said, “In the 20th century, networks of missionary hospitals in rural Africa found coronary artery disease virtually absent–and not just heart disease, but high blood pressure, stroke, diabetes, common cancers, and on down the list.”

Regardless, all three six-month studies showed weight-loss effects with a low-carbohydrate diet and didn’t apppear to cause additional health risk (where they looked at that), but none were technically long term. In addition, one of the studies concluded “This finding should be interpreted with caution, given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects.”

In other words, while there was a statistically significant difference in weight loss, it wasn’t that large a difference. Since Dashti’s study had the same number of subjects and no control group, we can assume the same caution is needed for it.

What we can conclude is that we still don’t have a long-term study. One reason for this is the high-fat diet is hard to sustain much longer thant six months. We do, however, have long-term studies for high-carbohydrate diets (which turns out are very sustainable for years), and what we find are consistent, widespread health benefits, especially when such diets are focused on whole foods. There are also numerous reseach studies available on the long-term negative health effects of a high-fat diet.

So while we continue to wait for an actual long-term study that indicates no negative health benefits for a keto-like diet, I will continue to eat my vegetables, and fruits, and whole grains and other delicious plant-based foods.