* I take my vitamin D3 in the morning. It's known for keeping one awake when swallowed before bed time. It can take up to 4 months, sometimes longer, to reach top testing levels - or another way to phrase it, to fill up fully with D3. I personally aim for a testing level between 60 to 70ng/ml. When I first began taking D3 I was taking 8000ius a day. Now I only need 5000ius in order to keep within the testing range I'm looking for.
I don't know of D3's effectiveness level for bowel conditions. You might think of D3 and its many uses in the body as a multi stage water fountain. When first supplementing, the body uses D3 for helping with bone strength. Then once D3 levels go higher, it is helpful at preventing cancers. And finally near the top testing range, D3 is thought to help fight against infections, relieve depression symptoms, help with winter blues, etc.
The most noticeable effects I have felt from D3 are increased energy, relief from winter blues when I lived up north, and I stopped catching a cold during winter time. Some feel the reason why we have a flu season is during winter the sun goes away for a few months for many in the US, resulting in D3 levels to drop.
* Another fat soluble vitamin I take is K2. Unlike other fat soluble nutrients, K2 remains in the body for a short period of time. There are two forms of K2 sold in stores. K2-4, the type of K2 found most often in nature from animals sources that have been pasture fed, only lasts a few hours in circulation. K2-7, the type of K2 we are most likely to eat in todays modern world as it is found in fermented cheese, lasts for 2 to 3 days if I remember correctly.
I take K2 twice a day, once in the morning, and once in the evening. And I take a supplement that mixes both K2-4 and K2-7 together. There is no test for K2 levels that I'm aware of. There is also no known toxicity to K2. People have been known to consume massive dosage amounts with out causing health issues.
The most noticeable difference I've noticed since taking K2 is that I stopped developing dental cavities. I wish I had known about this vitamin when younger, as with many with bowel conditions, my teeth began to fall apart. Additionally I have a dentist that is aggressive at doing preventive dental work. So I had a number of teeth capped in the front of my mouth that I probably should have said lets leave alone. They look awful in my opinion. And had I known about K2 plus the importance also of limiting or eliminating grains from the diet, for dental health, I could have saved myself some grief.
I've seen several articles on the benefits of K2, but one I recall on a paleo sight I visit.
"Vitamin K2, Menatetrenone, Weston A. Price Activator X…or Whatever…It’s Amazing"
http://freetheanimal.com/2012/01/vi...-price-activator-xor-whateverits-amazing.html
* With many avoiding and not adding much salt to foods any longer, I began to supplement with kelp iodine rich tablets. Salt is fortified with iodine. Seems goiters are becoming more common once again with people not eating as much iodine, with thyroid testing level issues developing.
From what I've read it can take a few months of supplementing with iodine to notice a different in TSH testing levels. One example I recall where it took 3 months for thyroid levels to return to normal ~
"Iodine deficiency is REAL"
http://www.trackyourplaque.com/blog/2009/08/iodine-deficiency-is-real.html
* Fish oil is another supplement I take. I guess for some it can take a few years sometimes to reach an optimal 10% omega 3 index.