You'll notice in the lists below that many Alexa skills are called by using trigger words like open, start, play and ask. While select skills require you to use specific terms, others consider them to be interchangeable and will work with some or all of these phrases. Over time you'll begin launching your favorite skills by the words you feel most comfortable using. Initially, though, it can be fun to play around with each.
For tracking your food, you can use the Track by Nutritionix skill, which lets you record your food intake using your voice, or ask for caloric values of foods. (Alexa does the latter by default.) Say things like, "Alexa, tell Food Tracker to log a cup of almond milk" or "Alexa, ask Food Tracker how many calories are in two eggs and three slices of bacon."
Note: Your Flash Briefing settings apply to all Alexa devices registered to your Amazon account, and all users in your home get access to the same Flash Briefing content. However, if you or anyone in your home has a voice profile, Flash Briefing automatically skips stories and news items you've already heard. To learn more, go to About Alexa Voice Profiles.