If you use a high quality curriculum option, in most cases the answer is not only 'no,' but your child will likely get ahead, especially in areas where they have natural talents and interest. Many students become better readers while homeschooling. Students also have the opportunity to gain a more 'whole' educational experience.
The curriculum lists we share in our courses all offer higher quality material and more engaging experiences than most public schools. Remember, in homeschooling many of the time-wasters found in schools are eliminated so there are more opportunities for depth and breadth. Even if you are just homeschooling for a year or two it can be a magical addition to your child's journey!