To lose back fat, you need to lose overall fat. You may be able to do this by following a nutritious diet and exercising using a combination of cardio and toning exercises. Genetics, diet, and lifestyle factors all play a role in where your body stores fat.

Here are some exercises that can help you lose lower back fat:
- Reverse hip raise with exercise ball
- Side jackknife
- Superman
- Dorsal Raise
- Deadlifts

It's important to note that you can't lose weight in just one specific part of your body, losing weight overall will help diminish your lower back fat. Aim to eat lots of leafy greens and lean proteins, and keep your portions small. Create an exercise routine made up of cardio and strength training to get the best results.