In last week's column I mentioned ketosis and ketones. Since I have limited word space for each column, I thought it would be good to circle back and cover ketosis and ketones a bit better.

There are a number of issues around using ketosis for weight loss. Can ketosis be used to improve athletic performance?

First, let us take a look at what ketosis is. Ketosis is a metabolic process that starts in your body when you do not have enough glucose or sugar from carbohydrates for energy. When the body does not have carbs to burn, it turns to fat and protein for fuel. Once you kick-start fat burning, these fats are broken down, which creates a buildup of acids called ketones. Ketones are produced from fat and proteins and turned into molecules called ketone bodies, that the body then uses for energy.

Ketones are naturally produced by your liver when fatty acids are processed and metabolized. In a diet where both carbs and fats are consumed, your body will completely metabolize the small amount of ketones that are produced by your liver. When you drop your carbs to a very low diet of 20 to 30 grams per day, your body will typically shift into ketosis. This does produce fat loss fairly quickly, but ketosis comes with a number of unhealthy side effects. When your body goes into ketosis it shifts metabolically which can cause fatigue, headaches and dehydration issues to name a few.

Increased fat consumption can also lead to a shift in your blood-lipid levels and, in some cases, spike your cholesterol. You can also see a drop in key micronutrients like iron, potassium and magnesium, leading to even more issues, leaving you feeling less than optimal.

Probably the scariest health issue around ketosis is referred to as ketoacidosis. Ketoacidosis typically occurs when the levels of ketones in your blood increases to a point where your body cannot process them. This leads to a poisoning of your blood and body, leading to potential health risks. Ketoacidosis effects production levels around key hormones which can disrupt insulin function leading to huge risks, especially for diabetics.

Shifting your body to a low carb, high-fat diet to trigger ketosis is not something you want to do without understanding ketosis and its effect on your body. Everyone's health level and body chemistry is different and ketosis is not for everyone. If you have preexisting health issues or are a diabetic, I can't stress this enough; check with your physician before you consider ketosis as a weight loss method.

Now, how does ketosis work in terms of exercise, fitness and body composition? Most physically fit people and athletes are already efficient at burning fat for fuel. Many athletes and fitness folks also place a big emphasis on protein consumption to build muscle. This leads to two questions: First, where and what role does protein play in ketosis? The second related question is around reduced-calorie diets, which always runs the risk of catabolic muscle loss. Catabolic muscle loss means a low caloric diet can cause you to lose muscle.

To answer both questions, it's important to understand that protein and fat are essential macronutrients to sustain your health and nutrition. Most of the carbohydrates we eat are in fact low on the life-sustaining, must-have nutrition in our body. Athletes and active fitness people know we need to get plenty of protein to build and sustain muscle. But too much protein and you will not induce ketosis; too little protein and you will start to consume muscle as a fuel source. Your body will use muscle to serve as an energy source if your fat and carb intake is too low. Finding the balance for active fitness folks becomes a bit tricky.

Fitness activity places a large emphasis on aerobic exercise and this also can add problems to a low-calorie diet, causing additional muscle loss. Understanding protein and muscle loss when you explore ketosis as a way to achieve body comp and weight goals is key. Your brain will use protein as a go-to in an effort to get more glucose for energy - this is called gluconeogenesis. This is why finding the correct balance of fat, protein and minimal carbs to induce and maintain ketosis is everything.

Ketosis as a weight loss approach is proven but comes with many risks. If you can get your body into a ketosis-adapted state you should be fine for a short time (four to eight weeks) with good results. Keeping your body in ketosis over a much longer period of time can create health concerns, so keep that in mind. The biggest challenge will be shifting your body into ketosis by reducing carbohydrates to under 50 grams per day from your nutrition plan. Most people just can't get their carbs down low enough to reach what would be considered a ketogenic diet.

For athletes and fitness folks, being ketosis-adapted offers a number of opportunities that can improve their fitness and performance levels. A combination of fasting and low carb eating can get healthy active folks into a ketosis-adapted state fairly quickly. Once you get there it becomes key to manage your protein levels to around 150 grams a day for your average person and get comfortable with lots of fats in your diet.

Some of the positive aspects of ketosis for athletes and fitness people is better weight management and muscle definition, think "six-pack abs." Even very lean athletes can see the benefits of fueling with fat since the average person's energy stored as fat is 20 times greater than that of carbohydrates in the body.

Various studies have shown better endurance and resilience in high altitudes for those who are ketosis-adapted. It is also important to note that studies found that strength performance did not change between athletes who managed a ketosis-adapted diet and those who did not. Bottom line, ketosis is not for everyone and can come with many health risks.

There is a lot of very good data showing it can be a great addition to your health and fitness, and equally as much information that it can cause harm. It all comes down to your individual health profile, so please be careful and understand your personal risks if you choose to use ketosis for weight loss or fitness gains.

Judd Jones is a director for the Hagadone Corporation.