Some info on ketones and ketosis from my diet site...
https://en.m.wikipedia.org/wiki/Ketosis
What are ketones?
Ketones are a normal and efficient source of fuel and energy for the human body. They are produced by the liver from fatty acids, which result from the breakdown of body fat in response to the absence of glucose/sugar. In a ketogenic diet, such as Atkins ... or diets used for treating epilepsy in children, the tiny amounts of glucose required for some select functions can be met by consuming a minimum amount of carbs - or can be manufactured in the liver from PROTEIN. When your body is producing ketones, and using them for fuel, this is called "ketosis".
How will ketosis help me to lose weight?
Most reducing diets restrict calorie intake, so you lose weight but some of that is fat and some of it is lean muscle tissue as well. Less muscle means slowed metabolism, which makes losing weight more difficult and gaining it back all too easy. Ketosis will help you to lose FAT.
Being in ketosis means that your body's primary source of energy is fat (in the form of ketones). When you consume adequate protein as well, there's no need for the body to break down its muscle tissue. Ketosis also tends to accelerate fat loss --- once the liver converts fat to ketones, it can't be converted back to fat, and so is excreted.
But, isn't ketosis dangerous?
Being in ketosis by following a low carbohydrate diet is NOT dangerous. The human body was designed to use ketones very efficiently as fuel in the absence of glucose. However, the word ketosis is often confused with a similar word, ketoacidosis.
Ketoacidosis is a dangerous condition for diabetics, and the main element is ACID not ketones. The blood pH becomes dangerously acidic because of an extremely high blood SUGAR level (the diabetic has no insulin, or doesn't respond to insulin .... so blood sugar rises ... ketones are produced by the body to provide the fuel necessary for life, since the cells can't use the sugar). It's the high blood sugar, and the acid condition that is so dangerous. Ketones just happen to be a part of the picture, and are a RESULT of the condition, not the CAUSE. Diabetics can safely follow a ketogenic diet to lose fat weight ... but they must be closely monitored by their health care provider, and blood sugars need to be kept low, and stable.
Does caffeine affect ketosis?
This is questionable. There ARE a few studies that suggest caffeine may cause blood sugar to rise, with consequent effect on insulin ... The studies involve consuming 50 gm glucose orally, followed by a dose of caffeine. This is quite different from a low carber, who is consuming only 20 gm carbs, in the form of high-fiber vegetables, spread throughout the day.
Many low carbers continue to enjoy caffeine-containing beverages with no serious impact on their weight-loss efforts. However, there are some sensitive individuals ... and persons who are extremely insulin resistant may need to restrict or even eliminate all caffeine. If you have been losing successfully then find your weight loss stalled for a month or two, and you are following your program to the letter, you might consider stopping all caffeine for a while, to see if that will get things started again.
Will drinking alcohol affect ketosis?
No and yes. The liver can make ketones out of alcohol, so technically, when you drink you'll continue to produce ketones and so will remain in ketosis. The problem is ... alcohol converts more easily to ketones than fatty acids, so your liver will use the alchol first, in preference to fat. Thus, when you drink, basically your FAT burning is put on hold until all the alcohol is out of your system.
This rapid breakdown of alcohol into ketones and acetaldehyde (the intoxicating by-product) ... tends to put low carbers at risk for quicker intoxication ... especially if no other food is consumed to slow absorption.
for Everyone!!
I'm not actually suppose to know that, am I? 
Congrats on your weight loss so far!
