My little guy has passed and I am just heartbroken. He had a stomach tumor?  I don't even know if the vet was right, it all happened so quickly.
He was my morning noon and night.
I hope that anyone with a cat gives them access to sunlight, all the time every day. Or at least once a week if you can't. As I can't let go of the guilt that he was an indoor cat.
They need microbes in the dirt, they need actual dirt to dig around in, it goes into their stomach somehow as they lick their paws and so is probiotics. I saw a video about it, and will put link at the end.
How can cats stay alive, if they don't have sunlight? They won't, they could develop disease just like mine, and I think my guy died too young.
I'm having a lot of guilt, if I didn't have the money to build an outdoor run, I was trying to, I could have built it with some fencing that's in a garden next to where I live. He had sunlight through the window and in his carrier but I don't think he had a lot consistently through his life. We had a deck a while back and he walked out a bit. The cat was lost for a few months, I found him after searching night and day, he bolted out the door once, so I was overly protective and wanted to make sure he would never run away. And they do, they will find any little crafty hole in any fence and bolt!
If you live in a city, take them to a park or drive them up on weekends somewhere, they need grass and dirt.
They need decent fresh food, most of the baked crunchy kibble is from diseased factory farmed animals or bi-products, and I think even good brands like neuman's own might not necessarily be good?  I vote for wild and ocean fish, not feeding cats actual animals, those animals have cancer anyway, or most of them. And green powder from a company called Compassion Circle which feeds vegan cats and believes they can be vegan. I am vegan myself, and had great difficulty buying beef rolls, even if I bought one or two. I think it's laden with bacteria or freak strange virus things (in frozen raw beef) and your cat could be a statistic if there's some strange bacteria in there, this abadi brand boasts "long life for your cat, fresh food, etc". I don't think so.

Give them sunlight and dirt constantly throughout their lives! Mine had it a few years recently here and there but not consistently on a regular basis, and places I lived I didn't want to let the cat run, didn't know if the cat would be snapped by a coyote. They need a cat run built. I lived in a shoebox in Manhattan and it wasn't a place to keep a cat, that was years ago. Even if you live in a city, find dirt and put it in a box so they can scratch at it. Sounds gross but it's true. There's microbes in there, some sort of probiotics. They don't belong on hard wood floors inside.

They should have spirilina powder and tumeric supplements their whole life, so should we.
You can double check with a vet or wholistic vet but I'm pretty sure it's fine.

The dirt thing:

Healthy Natural Pets- raw food is best

Markus Rothkranz

I'm so sorry you recently lost your little fur buddy.  I lost one of my furry friends after 15 years earlier this year.  It never gets any easier

I didn't click on the link, but I think you're talking about Soil Based Organisms, which are a form of probiotics.  We take them ourselves, but actually give our cats different probiotics. 

Yes, I agree cats should get probiotics, ours get them daily.  And there is certainly nothing wrong with getting sunlight, although cats can get skin cancer if over exposed to the sun, particularly white cats, so can use a little sun screen on their ears (they make sunscreen for cats since they groom themselves and would ingest bad stuff if we put human sunscreen on them,)  (this is true even if they only get sun thru a window!)  My own cats have no inclination for the outdoors.  We found them on our front porch when they were about 4 months old, and ever since then, they won't even go near the front door!  It's been 7 years now!  They seem very content to sit in the windows and watch the birds, so we set up bird feeders and bird baths just outside various windows for them, along with window perches. 

I also agree with you that kibble is not the preferred food for cats.  I'm not sure I would advocate an all fish diet however, due to high mercury in some ocean fish, which can cause issues, and some people believe too much fish can cause urinary issues.  And I definitely don't believe cats can be converted to vegans.  The are obligate carnivores.