What he can do is listen to you and make sure you feel heard, acknowledged and appreciated first. Then he can support you and show you he loves you no matter what you think about yourself.
2. They're not about him
Many of your insecurities were present before your husband came along. But some can pop up after the wedding, and especially after having children.
If you find yourself nit-picking at your changing body, graying hair or and dulling personality, it can be easy to look to your hubby to give you a morale boost. Maybe he relieves your troubles and lightens the mood, but don't let this "fishing for compliments" become a habit. You have to find your own inner beauty at some point; otherwise your inner demons will stay powerful.
On the other hand, if it's actually your other half that's started complaining about your appearance or your attitude, you need to let him know shining a light on what he doesn't like won't make it go away.
Instead he can focus on what he does want, what he can change about himself, and how these things will contribute to a better, happier relationship.
3. They can't be ignored
Maybe your husband thinks ignoring your comments and asides about yourself is the best course of action. But when it comes to ignoring you, he can make things worse if he's not careful.
Let him know he can deflect the negative by bringing up your positives, or by helping you reshape your perception of what you see as problems. He loves you, and he can see your issues as quirks, fun facts, or opportunities for growth.
4. Some of them won't heal
Insecurities can come from or leave deep scars. And some of them may never heal. But your husband needs to know that despite being unable to fix them, you still need his acceptance and support.
You both just may need to learn to live with unpleasantness and find a new way of coping with hardships. They may not go away, but you can come to terms with your insecurities and learn to coexist peacefully with them.
Your husband can help you overcome some of your insecurities with support and love. If he's not a natural at that game, teach him how to deal with the pressures of being you. Let him into your world and show him how it feels to live in your skin, then help him ease the burdens going on inside of you. Show him the right way to deal with things he can't control, so you can better deal with them moving forward.
Ultimately, your partner in life just wants you to be the best, brightest, happiest version of yourself. He just needs a little guidance.