Good points.  Also there is a difference between "we're skinny because we can't afford to be fat" and "our diet is healthy".  Japan after WWII was nearly a famine situation...anyone who's been there has noticed that the older people are, the shorter they are .  Any population which is so hungry that its height has been stunted isn't the example to emulate.

JS

"As to the first question, it seems clear to me that the range of variation is *wide*. Are you going to claim that no one will do fine (that is, lead a long a healthy life) on a high-carb diet with lots of grain? Go look at Asia."

Oxfam would dispute that billions of people eating little but rice have adapted and are doing nicely for it. Given a financial choice, all of these people would substitute higher-nutrition foods, including as much animal product as they can afford.

I would class that presupposition as an "extraordinary claim" that would require a lot of evidence across different countries, cultures, and economic classes.

Also it is important to keep in mind that regional diets vary a lot. There is no such thing as a monolithic "healthy Asian diet" except in the mind of someone ignorant of how Asians normally eat in various countries and regions.

Japan is a poor example of a typical Asian country in many ways. As it is wealthier, the population has much better access to a variety of quality food than other Asian countries.

But the traditional Japanese diet, which many revere and consider has spiritual properties, is boiled white rice, miso soup, and salty pickles, with fresh vegetables only in season and animal products only in tiny amounts. For decades the Japanese government has been trying to get the population to eat more like Okinawans, whose diet is heavy in animal products and vegetables, in order to reduce strokes and osteoporosis that generally have meant most elderly people are bedridden.

1. Salt isn't a big deal: your kidneys will excrete whatever you don't need.  

Furthermore, in reality, the main source of salt in our diet is prepackaged and processed foods (and restaurant entrees), which are usually full of salt that we don't even notice.  If you're eating like a predator and preparing most of your own meals, you'll only be adding salt to dishes which actually need it, and your salt intake will very likely drop substantially.

Between these two facts, I don't worry about it one way or the other.

2. Eat fruit after your meal -- it's dessert.  In general, eat your protein first, then your veggies, then your starch.  (Although it's fine to have them all mixed together...just don't start with the fruit or the starch.)

3. Marrow bones are great!

4. Frozen fish is fine if you don't mind the taste.

5. The ALA in flaxseed oil is very poorly converted to the DHA your body needs.  Instead, I recommend consuming fatty fish 2-3x/week, or taking fish oil.

sunil:

I avoid beans in general.  

That being said, the occasional serving of dal can be delicious, and it certainly won't kill you...but meat, fish, and eggs are superior sources of protein, vegetables are superior sources of nutrients, and root vegetables are superior sources of starch.

Coconut oil or ghee?  Either one is great!  Paul prefers ghee, but several other people I know prefer coconut oil.  I use both depending on my mood.

JS

They're both good fats - either will do. As a cook, butter/ghee tastes better.

2, is eating fruits before your meal would be better or after.

3, is eating morrow bones on occasion fine or bad.

4, is eating frozen haddock is the same as fresh.

5, eating tablespoon of flaxseed after meal.

Then you need to increase that number until you stop losing weight.  

It's certainly not a protein shortage...if you're eating 40% protein calories at 2200 kcal/d, that's over 200g/day of protein!  It's very rare that I'll ever say this, but you need to increase your carb and fat intake.  For leaning-out purposes, make that fat coconut oil.

JS

If you're managing to lose muscle on a 40% protein diet, you're not eating enough food. 

Paleo foods, being nutritious, are far more satiating (and sating), per calorie, than processed foods...so if you're eating to the same degree of satiation that you were before, you're very likely to be eating less food than you were before.  (Total up your calorie intake on something like fitday if you're curious.)  If you were weight-stable before, the likely result will be weight loss.

Fortunately the solution is simple: eat more food! 

JS

30% of my calorie comes from fat, 30% comes from carbohydrate and rest from protein.

You're not going to find a "six-pack diet" that doesn't involve some amount of misery.  Look up "cyclical ketogenic diet", "Velocity Diet", "protein-sparing modified fast"...or just suck it up and use Jamie's, which I already linked above.  

Paul:

I tend to agree.  Yes, there are a few men who sport a six-pack on any diet...just like there are a few women who have natural E cups.  However, they're rare.

Rita:

The point is to eat in a way that allows us to reach our full potential as humans -- strong, smart, and healthy.  If you just want to get as lean as possible, see my reply above to kacper.

jason:

If you want to lean out:

-Go much higher on the protein and lower on the fat...i.e. leaner meats

-When you eat fat, make it coconut oil whenever possible

-More vegetables

-NO PEANUT BUTTER.  It's incomplete protein and a whole bunch of omega-6.  Peanut butter is not part of this diet!  I suspect this is a big part of your problem right here.  I'd ditch the other nuts, too, for similar reasons...most aren't as bad as peanuts, but they're calorie bombs and not all that nutritionally dense.

-NO SNACKING!  You don't lose fat if you're constantly snacking.  Either fix a meal or suck it up.  And if you can't go between meals without snacking, either you didn't eat enough or you're still not fat-adapted.

-Go easy on the fruit, and only eat it as dessert -- no between-meal fruit snacks

Let me know how this goes for you.  Remember, there is also the possibility that (depending on what you ate before) your body is simply stocking up on nutrients it hasn't had for a long time.

JS

Maybe knock down the fruit - one a day as part of your five a day, the other four being veggies, one or two of which can be carby roots.

Do predators graze their way through the day snacking? Nah! They stalk, kill and eat. It's what they eat that grazes.

Good that you've knocked out the processed food - real food talks little thought or preparation. Just clean and peel where necessary, cut, cook. Easy. That really is all there is to it.

i eat 5 fruit a day (banana, apples, mango, water melon, cherries and pear) more red meat, more eggs, canned wild salmon, more potatoes and finally i eat dark chocolate.

i eat a lot of fat such peanut butter, olive oil, red meat and eggs including yolk.

sometimes when i snack i usually eat peanut butter, almond or fruit.