I still think that radioactive particles are the key to cancer from smoking, moreso than any other factor such as acrolein.
That said, all things that hamper the body's natural protection and detox systems all add up to trouble. My best guestimate is till that vaping is circa 100x safer than smoking. If you are not averse to PG, make that at least 1/4 of the liquid you use (rather than all VG base).
Healthy life:
Reduce stress (many options here)
Avoid trans fats / margarines / 'long life' foods
Reduce sugars / junk foods
Indulge in spices, herbs, vegetables (esp tomatoe concentrates, garlic, onion, blueberries and other bright colored veg and fruit)
Have a glass of red wine in the evening
Enjoy sunshne and exercise but dont over do either *
This is it - make the best of your life; forget all negative stuff and radiate joy
Number 1 recommendation is reduce stress; it's even more important than stopping smoking! And can be just as hard to do ... But give it time, observe, and one step at a time ...
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Read up on vitamin D and its role as like a hormone to understand its importance to health.
Exercise id good for muscle building and fat reduction, suppleness etc, but there is a price - increased oxidation potential - so be sure to boost your diet / vitamins, otherwise exercising will age you faster