LAS VEGAS – Keeping track of everything you eat can help you lose weight, but it isn't always as easy to track your every snack and sip as it is to, say, clock how long you jogged today. But now, new gadgets aim to make food tracking easier and more precise.

The DietSensor scans your food with an infrared beam.
The DietSensor scans your food with an infrared beam.
Credit: DietSensor

One gadget, called DietSensor, claims to be able to scan your food with a beam of light and tell you its nutritional content, such as how much protein, fat and carbohydrates it contains. It does this by analyzing how the molecules in the food interact with the light, according to the company, which presented the device here at CES.

It works like this: The scanner sends an infrared beam onto the surface of the food. This causes the molecules in the food to vibrate, and produce an optical signature that is unique for that food, the company says.

But there's a catch — the scanner only works for homogeneous food, or food with one layer. So it would be able to scan a slice of bread, cheese or chicken, but not a chicken sandwich. You also have to manually enter the portion size. There is a database for nonhomogenous foods, which you can use to manually log food, athough this basically works the same way as existing food apps, like MyFitnessPal. [The Best Calorie Counter Apps]

Still, the DietSensor app displays the nutritional content of the food you scan, and also provides advice based on your goals or the conditions you have, such as diabetes or high cholesterol, the company says.

The scanner, which was developed by a company called ConsumerPhysics, is available for preorder at $249. The DietSensor app will launch in September.

The HidrateSpark smart water bottle knows how much you drink.
The HidrateSpark smart water bottle knows how much you drink.
Credit: HidrateSpark

Another new product doesn't track your food, but instead keeps track of how much water you drink, with the goal of keeping you hydrated. The smart water bottle, called HidrateSpark, contains a sensor that can tell how much water you drink, and connects with an app on your smartphone.

The app also gives you a personal goal for how much water you should drink, based on an equation that takes into account your age, height, weight, gender and even the ambient temperature and humidity, the company says. The equation will also take into account your activity level if you allow the app to access data from a wearable device like a fitness tracker or pedometer. (You can also input your activity level manually.)

A tube within the water bottle glows to remind you to drink more, the company says. The bottle costs $60, and can be ordered now, although the device won't ship until March, the company says.

The Smart Diet Scale weighs food to allow for more precise calorie and nutrient calculations.
The Smart Diet Scale weighs food to allow for more precise calorie and nutrient calculations.
Credit: Smart Diet Scale

There's also the Smart Diet Scale, which allows you to weigh your food, letting you more precisely calculate the calories and nutrients in your meal than if you just eyeballed it, the company says. Users put an item on the scale, like fresh chicken, and then can either scan a bar code for the item, which would find the item automatically, or manually enter the name of the item in the app.

The app contains nutritional information for more than 400,000 items with UPC codes, the company says. The scale is also sectioned into quadrants for users to weigh up to four items at once. The Smart Diet Scale is available now, and costs $150.

Follow Rachael Rettner @RachaelRettner. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.