The report uses CYA language notably in a few places.
there are also risks. "Deficiencies in nutrients like vitamin B12 or iron are possible
a purely vegan diet can result in potential health risks, because a plant-based diet makes it more difficult to ensure an adequate supply of some specific nutrients. Alongside vitamin B12, there are, for example, several minerals, certain amino acids and long-chain omega-3 fatty acids that are seen as potentially critical nutrients.
Notice that at no time do they use strong language. they are pretty much just warning of possibilities. Which from my own experience is plainly a smart thing to do. I've met a few vegans who are not aware of what kind of nutrients they may become deficient in*.
I would also like to point out that there are mitigation measures for all those concerns.
"the DGE does not recommend a vegan diet for pregnant or nursing women, infants, children and adolescents".
This is maybe the strongest sentence in the whole report. And although Vegan organizations conclude that the diet is safe for those groups, there is no denying the fact that those are the most vulnerable groups. They need to take the most care. It's probably the DGE's view that there is a lot of risk to those groups and they would rather just avoid it.
The majority of respondents have an awareness of the risks of this special form of diet....The survey highlighted the uniformity of attitudes...
In other words, most vegans know what they are doing.
there is probably no convincing your family
It became apparent during the course of the study that portraying a vegan diet as dangerous or abnormal does hardly reach the target group....
This could include concrete guidelines which vegans can integrate with their nutritional preferences."
So the take-away for your family is that even the DGE thinks telling vegans to stop being vegan isn't going to work. If they are Really concerned, they could just start sending you B12 and iron supplements. Where I live I can have redipacks of fortified soy milk delivered to my door. Is that available where you live. They could buy you a subscription. Ask for the six pack each week.
In many studies, some of them in Europe they have found significant percentages of the population to be deficient in B12, Iron, iodine, and vitamin D. The number of people that are deficient is much higher than the percentage of vegans. So... my takeaway is that they should put just as much if not more attention on educating the general population. that could help some vegans too.
Ha! turnabout is fair play. you should start quizzing them on their fiber intake. And D, B, Iodine etc.