It's a personal preference. Younger eyes see differently than older eyes. If you already have an overhead fixture, just buy a 2 or 4 pack of bulbs in each of the three commonly available color temperatures. Put them in and see what you prefer. Return the other ones or use them elsewhere. Three 60-watt equivalent LED bulbs are enough for many medium size kitchens' overhead fixtures.

If you are interested in LED technical details, the wikipedia article on LED bulbs is comprehensive. If you are interested in the color of sunlight as it hits the ground, it varies during the course of the day as the sun's altitude changes. At noon in mid-latitudes, it's about 6000 K.

Thank you!

Stating "4000K is correct" may have made you a particular Houzz member become your friend for life.

For the wattage in terms of what you are asking, you will be seeing "lumens" for LED's, and that's going to fall within a set range for a specific size and shape of 'bulb' you get off the shelf at the big box store. That just means you won't necessarily have much choice for lumens unless you dig deeper into sources, which isn't needed in this situation.

The testing of 'bulbs' as apple_pie suggests is the best advantage of using 'bulbs,' so you can experiment how you interpret colors/sheen of your finishes, shadows, and adjacent spaces interacting with each color temperature you try.

I would not want my house to have 4000K lighting, way too clinical/commercial looking for me! I prefer 3500K, but they are harder to find. You also need to consider Lumens and CRI.

No, 4000k LED is not correct for a kitchen. There is ONE Houzz commenter on this forum that says that 4000k is correct for a kitchen, and she says it over and over, on hundreds of posts, so that it seems like it is being recommended a lot if you don't notice that it's the same person saying it over and over. LED lighting for a kitchen should be 2700k-3000k. The 4000k level is for a hospital operating room or if there is a family member with visual impairment.

Placement of the lighting is important. Ceiling cans should be placed along the perimeter of the upper cabinets, about 12-18" from the edges of the upper cabinets. Undercabinet lighting should be placed toward the front of the upper cabinets - though contractors like to place it toward the back because it is easier for them and will save them 15 minutes. If you place undercabinet lighting toward the front of the upper cabinets it will shed light onto the center of the counters beneath them where it is most needed.

Hahaha thank you everyone! This was both enlightening and entertaining!!

The CRI rating is what you need to pay attention to for true to life colors. CRI is independent of the Kelvin rating for the lighting temperature.