友人にVegan がいます。
彼はいつも「Humans don't need meat 」と主張しております。
さらには、「Humans don't need meat to be healthy」と言う事で、健康的なところを主張します。
彼に言わせてみれば、動物愛護の動機が強く、肉を食べることを拒んでいます。
彼は肉を食べることを「It's cruel to animals to eat them」と言います。
その方が響があるみたいです。
個人的には、肉を食べる量を減らしています。
何故ならば、彼の言葉に刺されました。
特に、肉料理の写真を送った時に、「You're eating so much death」と言われた時に「確かにそうだな」と思いました。
"Humans can stay healthy even without eating meat."
「人間は肉を食べなくても健康でいられる」"stay healthy"は「健康でし続ける」と直接和訳されるんですが、「健康に生きていける」という意味を持っていると思ってもいいです。
あと、英語では「肉」は"meat"といいます。
こういう言い方もあります：
"Humans don't need meat to stay healthy."
「人間が健康にいられるために肉を必要とするわけではない」
参考になれば幸いです。
Meat is not an essential part of a healthy diet for us
People may choose to remove meat from their diets for a variety of reasons, such as supporting animal rights, reducing the environmental impact of meat, to improve their health, and for religious reasons.
People who avoid meat are called vegetarians. People who avoid all animal products and meat are called vegans.
As someone who has not eaten meat for most of my life, I frequently have people approach me with concerns that I must be deficient in vitamins and minerals due to my meatless diet. Unfortunately there are still many misconceptions about the role of meat in the human diet.
Perfectly well' is an expression that may be included in any situation where you are ascerting the ease and problem-free conditions in which any task or process may be completed.
Eg. John is perfectly well aware that he must meet James at the railway station."
Eg. Henry accepts perfectly well the idea of sharing his workload with Mary."
「Perfectly well」は、仕事やプロセスが容易に問題なく完了できることを強調する場合に使える表現です。
例）
John is perfectly well aware that he must meet James at the railway station.
（ジョンは、ジェームスと駅で会わなければいけないことは完璧に分かっています。）
例）
Henry accepts perfectly well the idea of sharing his workload with Mary.
（ヘンリーは、仕事をメアリーと共有するということを完全に受けいれています。）
Human can still be healthy without consuming meat.
When you want to explain that humans can still be healthy without eating meat, then you may say this in the following ways:
-Humans can live healthily without eating meat
-Human can still be healthy without consuming meat.
「人間は肉を食べなくても健康に生きていける」は次のように言えます。
-Humans can live healthily without eating meat
-Human can still be healthy without consuming meat.
（人間は肉を食べなくても健康に生きていける）
People who don't eat much meat are usually healthy.
A diet that doesn't include much meat is healthier for people.
Some other ways to say "Eating less meat is healthy" are:
1. People will live longer if they eat less meat-this is an easy way to say the eating less meat is can make a person live longer.
2. People who don't eat much meat are usually healthy.-this is an easy way to say that eating less meat is healthier for people.
3. A diet that doesn't include much meat is healthier for people-this is a more detailed example of explaining that less meat leads to a healthier life.
"Eating less meat is healthy"（肉を減らすことは健康にいい）は、次のように言うこともできます。
1. People will live longer if they eat less meat（肉を減らした方が長生きできる）
→これは「肉を減らすと寿命が延びる」のシンプルな言い方です。
2. People who don't eat much meat are usually healthy.（あまり肉を食べない人はたいてい健康です）
→これは「肉を減らすことは健康にいい」のシンプルな言い方です。
3. A diet that doesn't include much meat is healthier for people（肉の少ない食生活の方が健康的です）
→これは「肉を減らすことは健康にいい」をより詳細に伝えています。
おっしゃられている内容は、以下のようにも表現できると思いましたm(__)m
Humans can stay healthy without eating meat.
「人間は肉を食べなくても健康なままでいられる」
stay healthy「健康なままでいる」
without ～ing「～せずに、～しないで」
以上です。
少しでも参考になれば幸いです(*^_^*)
These three phrases can all express how a vegetarian diet or a diet without meat can still be healthy. We can use phrases such as, "to not need," or, "is not necessary," to express that it is not as important for something.
We can also use, "to be able to be healthy without," to show that something is possible (to be able to) without something else, such as eating meat.
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