All you have to do is go 10 days without eating meat, which means coconuts, potatoes, fruit, and canned beans are all good. This is extremely easy; eating is so overrated in this game. Starting with full hunger and health meters, it takes about two days for your hunger meter to empty. Once you have the Starvation debuff, it takes about four days until you die. (This time is variable because Starvation does not deplete your health meter while you sleep. Generally speaking, the earlier you go to sleep, the longer you sleep, so it helps to go to bed as close to 18:00 as possible.) Bottom line: you can go 6+ days without eating ANYTHING, so all you have to do for the achievement is stretch it another 4 days.
Contrary to popular opinion, you can eat as many coconuts as you want as frequently as you want
. Drinking too much coconut juice
is what makes you ill. Simply chop them open without drinking and chow down. Eating 4 coconuts (8 halves) will fully replenish your hunger meter and add the Healthy buff, provided you keep your thirst meter filled also. Potatoes and fruit are super-foods, but go easy on the fruit, because it can also make you ill.
I unlocked this achievement by eating nothing but four coconuts, all at once, in ten days. If you don't want to go the starvation route, simply eat more coconuts, potatoes and/or fruit than this. Based on my experience, any part of a day counts as a day, so if you don't eat meat past 23:59 on Day 1, the achievement will unlock at 00:01 on Day 10.
If you plan to be mostly idle, it will take between 4 and 6 real-time hours, again depending on how much you sleep.
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