Lighting, Light Fixtures, Ceiling and Exhaust Fans - How many recessed lights on one switch?

Hi. I am remodeling our kitchen. I would like to do away with the one existing ceiling fixture in favor of 6 or 7 recessed lights. These new ceiling recessed lights would basically follow the "U" pattern of the soffit over the wall cabinets casting their light toward the counter areas below. They will most likely be installed about 10" or 12" from the soffit. Can I power all of these from the one electrical box that powers the old middle of the room ceiling fixture and its wall switch? If so can a dimmer switch handle so many recessed lights? I plan on using normal recessed lighting that can be aimed a bit. There is easy access from the attic to do the wiring. By the way, the ceiling is heavily insulated with loose fill insulation. Will there be a fire hazard from heat? I wasn't planning on using any low voltage lights but am open to suggestions.
Thanks in advance for any help.

Some recess cans can be in direct contact with insulation. These are IC rated cans. None should have insulation directly on top of them.

How many you can add to the total circuit depends on what is on that circuit now. Find the breaker that shuts off that light, then go around the house and see what all is not working. Make a list. Add up the wattages of everything. A 15 amp circuit should not be loaded beyond 12 amps. 12 amps at 120 volts is 1440 watts.

Your 15 amp switch would be able to handle this same wattage. Dimmers come in 500 watts then 1000 watts. It is not a good idea to max these out either. In addition the 1000 watt dimmers do not fit easily in a single gang of a multi gang box. For example if you have two switches in the same box now, adding a 1000 watt dimmer to that box, may require you to install a larger box.

To size the lighting leg of this circuit do the same thing as you would for the rest. Add up the wattages. 7 each 75 watt bulbs would be 525 watts. too much for a 500 watt dimmer, but not too much for a 1000 watt dimmer or standard wall switch.

I reccomend a trip to a local lighiting supply house. They can help you with all the details of your planning, and help you choose fixtures that will cast light in a way that is suitable to your needs. (lighting patters, or the foot print that they cast, are different for different types of fixtures and lamps.)

When you do your lighting wattage calculation you need to use the maximum wattage rating of the fixture not the wattage you intend to install. You also need to make sure your fixtures are a dimmable type.

Thanks for all this helpful information. I really appreciate you taking the time to explain how to calculate all this.
This forum is so-o-o-o helpful.