Listed below are many of the positive bodily changes I've personally seen over the years just converting to more raw veganism and having one or two stints of 1-3 weeks exclusively alone. That is all, and I'm certain more benefits come out of longer dedications to clean nutrition.
I've gone on and off over a dozen times so I can see the effects come and go and know that it does these things for my body. Obviously some effects take longer and you may feel some detox symptoms in the transition but many benefits I'd say the average to moderately health conscious person should see within a week.
My eyes become stronger, eventually don't get sore, and can look out in a sunny day without feeling any discomfort from the sun
More energy overall
Get to sleep easier/faster
Need less sleep and still feel energized
More energy overall throughout the day
Less bloating at first, then NO bloating
Less to NO constipation, bowels become very regular and solid, not-messy
Stop or reduce sweating a LOT
Lower or NO body odor, I've had different people attest to this and I don't wear deodorant anymore
Better temperature tolerance to heat and also cold
You feel much lighter on your feet
Higher endurance for general activities
Faster recovery from workouts
Lose that sense of feeling hungry in the same way
Much lower water need daily (fruit is high water)
Faster digestion, stomach empties much faster
Hair/scalp stops getting greasy, less need for shampoo
Dandruff goes away
No more dry skin, skin is hydrated
Sunburns, much reduced risk if any at all - sun feels good and not a burning feeling
No more limbs falling asleep (caused by high sodium diet) - never get that tingly feeling again
don't get those 'sock lines' or whatever from laying on something, that pattern you seen indentation on your skin when you wakeup; this is from sodium causing water weight
No more weight management, eat as much as you want basically
sexual: body fluids taste a lot better
Don't get chapped lips anymore
less red eye, no more eyes worn out from monitors at least way better
Quicker restroom visits
Change in tastes to enjoy healthier food vs unhealthy
Wounds heal quicker
Suntan without brown spots on skin
I advocate the high carb (Fruitarian) vegan diet, also can be called 80/10/10 raw vegan or 801010rv - which allows a large salad at night and minimal avocado & nuts/seeds which I don't normally advocate
LINKS
RawKristina big raw vegan advocate &long-term, cured chronic issues
OTHER BENEFITS:
You can probably cure nearly any disease on this diet long-term (just like you could with using water fasting)
Research for a bit and you will find that people have cured: cancer, diabetes, IBS, Krohn's disease, MS, Asthma, Many allergies and way more!