I don't have enough donor hair for my transplant, I have been advised to use beard hair, should I proceed? (Photo)

If you don't have good donor hair and would like other options it is best to discuss it with your doctor.  You need to understand what is realistic and possible with the other options as well.

Hi. I am unable to see your donor area therefore it is difficult for me to give accurate advice. I perform many beard hair transplants for individuals who do not have enough donor area. But please be careful using beard hairs in the frontal hairline, as the aesthetic result is not desirable. 

Beard hair is a good donor area for permanent result(the down chin part area).The hair tissue on the head donor area and beard or chest donor area is different.In our clinic body hair transplantation we use specialy to increase the density for the top-vertex area.Its not recommended to use on the front line .

Thank you for your question.  The photo you have provided does not show the donor site and it is difficult to comment.  When there are limited donor sites then the option of beard or even body hair may be considered.

Generally using body or beard hair on the scalp is saved as a last resort. Other options, like SMP, should also be considered. But if you and your doctor went through the choices and settled on beard hair, there's nothing wrong with that from my perspective, considering I don't know very much about your particular case. If you have doubts talk to your doctor or see another in person for a second opinion.

Looking closely at your picture  you appear to have a lot of miniaturized and villus hairs. This means your main goal needs to be prevention of further loss and potentially strengthening the miniaturized hair you still have. You could consider any or all of the following preventions: minoxidil 5%, Finasteride, low level light laser, and possible PRP. Each works by a different mechanism so logically you could use one or all. I would give prevention a solid try for a year before considering beard or body hair. 
Beard hair is more successful than body hair, but results can be disappointing. 
Scalp micro pigmentation  is another possibility to consider.

Beard and body hair can be a good alternative for those who do not have quality scalp donor. You can also look in to PRP therapy. 

I am not sure why you don't have enough donor hair. I will assume that you had already exhausted your donor area and now want more hair or more fullness. This can be achieved with beard hair (may have a different characteristic than your scalp hair), body hair (a poor choice as it is less quality, or scalp micropigmentation (a good choice alternative for more fullness)

I never recommend using body hair or beard hair when doing a hair transplant. The results look unnatural and the hair from the beard and body are not the same as the hair taken from the head. I would recommend looking at other alternatives such as PRP or SMP to fill in areas that are still thin when you have used up the proper donor hair. 

Body hair including beard hair is difficult to remove with FUE because of the laxity of the donor tissue. Body hair has a much poorer survival rate than hair from the head. Proceed with caution. Each individual desiring hair restoration should be evaluated by a full time, dedicated and reputable hair transplant surgeon to develop a personal plan to combat hair loss. Finasteride is a good solution for many.