Is she lying, lucky, or is veganism not that bad? How can a body function after 90 years of guaranteed B-12 and DHA deficiencies, not to mention probable deficiencies of countless other nutrients?
There's a lot more to health than nutrition
Regarding DHA deficiencies, it isn't a foregone conclusion that vegans or vegetarians in general will be deficient - perhaps not optimal
In spite of being a vegetarian Paleo, I firmly believe that eating well-sourced animal products will maximize your chances for health. But YMMV! Do what works for you based on the scientific evidence you have before you and validate your n=1 experience FTW!
EDIT - to answer your question, yes it is "possible", but if health rather than ethical considerations is your objective, it does not seem "probable"
She does well on other aspects of longevity: (i) calorie restriction, (ii) stress control and (iii) exercise.
When my husband and I got married in 1922, we took some classes at the camp grounds and they taught us to eat two meals a day and walk fifteen minutes every two hours.
The oldest man in the U.S. died last year at 120 something and he ate only 2 meals a day: breakfast and lunch. He didn't touch anything after lunch. Two meals a day would amount to calorie restriction.
And walking a good distance everyday would keep her in good shape. But she also has stress under control, being a devout 7th Day Adventist (what many people miss) -- this gives her a sense of mission as well as fulfillment, something that modernity does not instill in people.
When asked how one might live to 108 and keep close to God, Dinwiddie replied, “Read the Bible... it's all in there. People say to me, 'you don’t have any aches or pains and you’re feeling great at 108, what do you do?' Well, do what God tells you to do. It is all in the Bible.”
Her cortisol and other hormones would tend be in optimal range. In short, her secret is CR and Tebowing. I wouldn't be surprised by any of this. Nor should anyone who believes in Norman Vincent Peale.
Plenty of anecdotes abound of centarians who smoke, drink, played in polluted rivers, ate blah blah blah blah blah. You gotta do what works for you and makes you feel healthy. Perhaps she never drank the soy kool-aid and eats mostly home made food. Maybe she's just blessed with a family line of people who DID eat healthy and she's just enjoying the fruits of her epigenetic wealth. Who knows how healthy her children are.
I sincerely doubt that she has been a vegan that long. I suspect she is misunderstanding what veganism is. It barely even existed as a concept when she claims she started the diet and when it was referenced during that time, it simply meant the same thing as vegetarian. I wouldn't take it seriously unless she can provide some real evidence she has been vegan that long. Either way, the importance of those nutrients is primarily during pregnancy and early childhood development. And of the people who are that old, most did not eat any particularly special diet.
She's just one example. She can't explain it herself (saying she does it because it's in the Bible.)
There's no such thing as luck, and I'll give her the benefit of the doubt and say she isn't lying. In the end it just reinforces the notion that we all need to find what works for us as individuals.
I made the Vegan Mistake for about 8 years, and though I would never recommend that anyone go down such a path of nutritional martyrdom, I will say that I would undoubtedly have been far healthier if instead of the grains, soy, and other crap, I had just built a diet around tubers and fruit. Many deficiencies would still have been encountered, but I suspect that the mineral deficiencies I ended up developing would not have occurred/been as severe.
I recently spoke with a vegan and told her as much but she looked at me like I was speaking another language while she ate a plate of tofu. Can't say I didn't try.
Now, a tuber/fruit diet + plenty of pastured eggs would probably not result in any deficiencies.
This question aptly demonstrates the amazing power of the single-case anecdote to shut down critical thinking. The longevity of this 108-year-old person who may be a vegan tells us very little about that person's life in its entirety. Including her genetic endowment, or her mindset.
When asked, “When did you become an Adventist?” She answered, “When I was born.”
Would that be a 7th Day Adventist? I have read several times that they have a higher life expectancy than the average American. Part of the reason for their longevity is said to be their community spirit. Same thing with the Mormons and other communites known for their longevity.