The easiest way to get in shape is to ask yourself “did I move enough this morning/afternoon/evening?” Every day and also “is what I am planning to eat this morning/afternoon/evening/right now healthy?”

People know the answers to both of these questions. If you’re overweight or have high cholesterol the answer is usually “no” to both of them. The challenge is motivating yourself to eat well and exercise. IF is great, dieting is great. The problem is that they are always temporary solutions to a willpower and lifestyle problem that needs to be addressed to see lasting success.

IF is interesting because while it definitely has benefits, I have no idea if they’re specific to IF or incidental to the fact that you’re consuming fewer calories in general when you’re fasting. Like IF has obvious benefits, but are they superior to the same level of caloric restriction spread over three meals throughout the day?

Put another way, if I am going to eat 1,400 calories in a 24-hour period, does it matter if I only eat them between 8am and 2pm, vs. any time in that 24-hour period?

I think the only consistency in IF studies is that it works, but not because of IF science—it’s just another way of caloric restriction dieting that requires less planning and fewer temptations.

They’ve been working on anti-air lasers for years so this is a pretty landmark development in laser tech.

Ashkenazi Jews descend from a very specific ethnic genetic lineage. I realize I could convert and no longer be Jewish, or someone with no genetic relatives who are Jews could convert into Judaism. I realize your belief doesn’t change your genes and vice versa.

But Jews who come from other Jews who were born Jews tend to come from a specific genetic family tree, one that came to Europe with the Romans as soldiers, slaves, merchants, and sometimes even royalty, where many took European spouses and had babies that were roughly half European and half Levantine. Which is why Ashkenazi and Sephardic Jews have European genetic features. The key though is that due to prejudice, at certain pivotal moments and places in history, the European admixture was severely limited and Jews were murdered in medieval quantities that approach genocide. This resulted in genetic bottlenecks described in the article.

The challenge then is the mystery of which European community or communities created the bulk of the Ashkenazi European genetic family tree. There are a lot of theories involving everything from Carolingian France (tolerant of Jews) to Germanic pagans along the Rhein to Italians and other mid-late Roman Empire peoples. The truth is probably a little of all of this, since many Catholic and Lutheran Europeans also have Jews in their family trees dating back to medieval times.

But generic bottlenecks create major challenges in identifying admixture populations because the genes themselves don’t have racial or religious traits, they can only be used to compare to other generic populations to source a common ancestor. The problem is that when prejudice and genocide severely limit a genetic community to a small population of founders, your genes resemble that community far more than any other community, creating a distinctive genetic pattern that is hard to match with others. So while we know that Ashkenazi and Sephardic Jews have European admixture, it’s currently impossible to identify with certainty who those people were.

As a fully AJ Jew I’ve always hoped we’d one day know who our European admixture ancestors were. Sadly I dunno if the genetics will ever be able to climb that hill since the bottleneck was so extreme 1,000 or so years ago. I’d just love to know if my European “half” is Italian, or early German, or French, or whatever. But they killed so many of us and created such a generically distinctive line of survivors that it’s probably impossible to say.