Well, maybe you don't consider it food, but its the most important thing you can take along. Don't even think of starting on a hike that takes you more than a mile from home without a bottle of water along. You should have at least two quarts of water with you and drink 1/2 to 1 cup every 30 to 45 minutes. Keep the water coming into your body even if you don't really feel very thirsty. If you are hiking, you are losing moisture and you need to replenish it.
By the end of a 4 hour hike, you should have drunk both quarts of water and you should be able to use the toilet. If you don't need to, then all that water came out as perspiration and you still need to drink more water to stay hydrated. After a hike, you should drink additional water until you need to use the toilet. I don't mean chug it down, I mean drink a 1/2 cup or so every 5 minutes or so.
I have sitting in front of me a large bag of Kirkland Trail Mix from Costco. One ounce (28g) contains 150 calories. Of those 150 calories, 84 (or 56%) are Fat. Ouch! So much for the healthy trail mix fairy tale. It sure tastes good though, and some of it is just fine, but not handful after handful. You can see a Trail Mix recipe if you'd like to make some.
It's fine to consume more calories when you're in the outdoors burning off more calories than normal but you might as well make a bit of an effort to eat healthy food. One day of hiking and eating high-fat food probably won't hurt, but it also won't make the hike any more productive. Calories from simple sugars, complex carbohydrates, and fats are useful in different ways to your body. For ongoing energy boosts while hiking, the quickly metabolized carbohydrates should be preferred.
Here's a table of some foods, their approximate calories in 28g, and amount of carbohydrates, protein, and fat:
| Food | Calories | Fat | Protein | Carbs |
| banana | 97 | .5g | 1.1g | 24.7g |
| dried apple | 68 | .1g | .3g | 18.5g |
| dried apricot | 67 | .2g | .9g | 17.5g |
| raisins | 84 | .2g | .8g | 22g |
| tuna | 33 | .2g | 7.2g | 0g |
| cracker | 142 | 7g | 2.2g | 17.4g |
| cheddar | 113 | 9.3g | 7g | .4g |
| granola | 137 | 6.8g | 4.2g | 14.9g |
| granola bar | 137 | 6.7g | 2.8g | 17.7g |
| peanut butter | 165 | 14.3g | 7.2g | 5.3g |
| peanuts | 170 | 14g | 7g | 5g |
| jerky | 116 | 7.3g | .4g | 3.1g |
On day hikes, carrying a couple apples or other fresh fruit probably won't tip the scale on your pack and they include important water that you'd need to carry anyway. On longer treks, drying your own fruit is a great way to reduce weight and still get healthy food.
Grain is also a good source of carbohydrates. Breads and crackers are a good choice for day hikes.
You can find these fancy treats in grocery stores or pay more for them at outdoors stores. They pack a lot of calories in a small, heavy bar but you may have to eat a few before finding one that you enjoy. I've gone through quite a few and most just don't taste that great to me. I do like the Lara Bars pretty well and some Clif Bar flavors are good.
| Bar | Weight | Calories | Fat | Protein | Carbs |
| LUNA | 48g | 190 | 6g | 9g | 27g |
| Power | 65g | 240 | 3.5g | 10g | 45g |
| Clif | 68g | 250 | 2g | 10g | 51g |
| Lara | 48g | 190 | 9g | 5g | 24g |
| Peak | 77g | 300 | 6g | 20g | 48g |
Dried meat isn't a source of carbohydrates, but it is a nice treat on the trail. I really prefer home-made jerky since I can spice it just how I want and make sure its as dry and chewy as I want.
Be sure to take enough hiking food with you on your outings and try to keep it healthy. After all, you're out there to enjoy nature and do good things for your body, so you might as well give it good food for fuel. Treats like trail mix are fine in moderation and drink lots of water!