Simple question, would there be a benefit to eating only vegetables and a little fruit once or twice a week and then the other days eating a paleo style diet? Intermittent fasting allows 500 calories during the day (without protein) and that would be hard to make up with vegetables.
I tried it today and feel pretty good so far.
I usually do a full fast (36 hours with no food at all) once every couple weeks but if I didn't then i'd make sure to have days where I go very low on protein. I generally restrict protein to around 75g per day aswell.
If you eat lots of protein then you're going to keep your cells in grow mode & potentially prevent your body cleaning itself up (autophagy), so going low on protein once in a while, like one day per week, isn't a bad idea IMO.
I would actually say essentially the opposite of @jake3_14. Animal product should strategically supplement a plant-centered diet.
Nutrient density: plants beat animals per calorie, most of the time. You can find exceptions, but they aren't the norm. Lower bioavailability is a potential issue, but that simply means you should be eating more veggies! Retinol needs are rather low, so between beta carotene conversion and a little dietary retinol, you'll meet needs. Same goes for DHA/EPA… ALA converts to DHA/EPA in the amounts humans need… plus the little bit you get from animal products… adequate.
You don't need all nutrients everyday. If you go vegan for a day, you'll likely meet all nutrient requirements, except for B12. And most days, eating meat, you will get 100-200% DV of B12. So you're good (we have reserves of B12, plus it's recycled in our bodies).
EDIT: The above is more a response to Jake. To answer your question, would it be beneficial to eat a 500 calorie menu of vegan foods once or twice a week? I don't see the benefit, but there's likely no detriment either.
during the summer, when my garden is in full swing (like right about now) I may go a couple of days without eating meat (or at least much meat). As long as you are getting the protein you need (I typically consume a protein whey drink every day) -- 6-12oz of meat per week is sufficient (i'm probably about double that). When you eat less, you can also afford higher quality meat -- e.g. a nice 3oz wild sockeye or a 4oz grass-fed prime filet.
As far as "paleo" is concerned -- I'd imagine that in spring and summer when fruits and vegetables are abundant, Grok was fairly opportunistic...
Safe — yes; optimal — no. The most basic reason for eating animal protein is nutrient density. Plants, by their very nature at the bottom of the food chain, are low in nutrients and often contain nutrients in forms that the human body is poor at converting to a usable form. An example of this is in spinach. It has a lot of iron, but it's non-heme iron, completely unusable by the body. Another example is flax, which is high in short-chain omega 3 fatty acids. That form, however, requires a 5-step process by the body to convert it to the long-chain O-3 fatty acid DHA, which is what the body actually uses. This conversion process is frequently broken in people, due to insufficient production of the necessary enzymes. A third example is beta-carotene. Vegetarian advocates assert that we can convert this chemical to vitamin A, but the fact is that humans are very poor at this conversion, and end up converting 5% or less of the beta-carotene in a plant into vit. A.
Conversely, animals concentrate nutrients and store them in forms directly useable by humans. Liver and eggs from traditionally-raised animals are full of retinol, the bioavailable form of vit. A. Beef liver, and to a lesser extent, beef muscle, contains heme iron. Pork fat is 50% omega-9 fat (oleic acid), which plays a role in telling your brain that you're full. The other 50% is a mix of saturated fatty acids — stearic, palmitic, myristic — that are involved in cell messaging and immune function. In particular, palmitic and myristic acids function directly as signaling messengers that influence metabolism, including such critical jobs as the appropriate release of insulin.
Vegetables should be considered adjuncts to animal products in a paleo diet, not replacements.
You can eat veggies and meat together, they both provide benefits. 500 calories a day is undereating and if you do it for the long term it can be problematic - Intermittent Fasting is about restricting the timing of the food, not the calories; you'd eat the same amount of food that you'd eat within a day, but inside of a shorter eating window, say 2pm-8pm.
It's perfectly safe to do a 16/8 IF daily, but if you also calorie restrict, you'll quickly get into trouble and slow down your thyroid and stress your adrenals....
There are many styles of fasting, one is a protein sparing fast (usually done to lean out) where you only eat protein and nothing else, another is a protein eliminating fast where you don't eat any protein - but in this form you'd be certain to avoid all protein sources, even ones from vegetables - so you'd stick to eating pure carbs or more likely pure fats. They both have their benefits depending on what your goals are.
The paleo diet does not exclude veggies, infact, we probably eat more veggies than most vegetarians on the average. So the question is, what are your goals and what are you trying to achieve?
Eliminating meat, just for the sake of doing so is silly at best, and smacks of pandering to Meatless Mondays. I prefer eating meat on any day whose name ends in the letter "y" - unless I'm doing a protein free fast, or a 24h fast, and honestly, I almost never do those - those are only for entering autophagy and limiting any possible cancerous cells from growing.
Too much protein can be toxic, so that's the reason for a protein free fast day, but even then, the ideal is to limit all protein intake daily and avoid going over your needs, not to eliminate it two days a week, just because. When we don't get enough, we catabolize our muscle stores for this, which isn't a good idea.
If you don't do resistance training 0.8g/pound of lean body mass is a good measure of protein intake, 1.2 if you do resistance training. Doing something like 2g/lean body mass is not a great idea. Keep in mind, a gram of protein isn't a gram of meat - meat is 25%-33% protein, so you'd need to multiply the grams of protein by 3x or 4x.
Remember, we need some protein daily to do repairs. There's no reason to attempt to get this from just veggies, and it's much harder to do since you have to plan your meals very carefully, it's just far easier and simpler to get your aminos from meat and not worry about it.
Other than not developing an intolerance to the animal foods you eat, or practicality I don't think there are any advantages. But you can change your animals to avoid intolerances also, such as ruminants-fish-shellfish-poultry...
Dear HuntingBears, intolerance is a real thing and may occur when you eat sth consistently, there are many whole books on it:
I hope you'll either explain me why it deserved a minus or thank for saving your ass in the future
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