I hear this question asked often. Most of the people who are always hungry are the ones who are eating processed foods. The chemicals in processed foods hijack your hunger circuit. What exactly have these food companies done to get you addicted and keep you coming back? I read Steve Witherly's, "Why Humans Like Junk Food" and will break down his 208 page book into a few paragraphs for you.
Junk food companies have found the perfect storm to making their foods irresistible and keep you coming back for more. They have scientists that have come up with ways to keep you hungry and wanting more.
The Food Pleasure Equation The combination of taste (sweet, salty, umami- deliciousness), aroma, texture, food meltdown, and memory.
Think about eating BBQ Pringles (I used to love these). 1. They are sweet and salty at the same time. 2. They smell like BBQ. 3. They are rough and crisp. 4. They make a crunch when you eat them but then they are soft in your mouth and go down easy. 5. Everyone remembers making duck faces with Pringles and watching actors do it in commercials. Do you want some Pringles right about now?
According to food scientist Steve Withers:
When you have a food choice, the brain actually calculates how much pleasure will be generated during the eating and digestion of a particular food. The goal of the brain, gut, and fat cell is to maximize the pleasure extracted from the environment, both in food sensation and macronutrient content. If a food is lowered in calories for health reasons, the gut has the ability to sense this, and the food will become less palatable over time
His theory gets much more complicated by adding in things like combining opposing tastes and textures- sweet and salty, crunchy and creamy.. etc. But, what everything breaks down to is providing the brain with a pleasure sensory experience. They keep you wanting to come back for more, but that doesn't explain why you're still hungry.
You're still hungry because of these top four chemicals in processed foods: High fructose corn syrup, refined flour, refined sugar, and MSG.
High fructose corn syrup slows down the secretion of leptin in your body. Leptin is the hormone that signals your brain that you are full and to stop eating.
Refined flour as stated by Dr. Louis J. Aronne, causes ‘fullness resistance.’ It raises your blood sugar levels very quickly. This causes a spike in your insulin levels and but then the levels quickly plummet. Your blood sugar comes back down, and then you hungry again.
Refined sugar gives you that feeling of needing a "sugar fix" in the afternoons or evenings. You just get this random craving that comes on where you need something sugary. Eating refined sugar causes your blood sugar level to spike and then immediately fall again. This is why you need that sugar fix.
MSG is a powerful taste enhancing amino acid. As Witherly stated, your brain wants to replicate the pleasure feeling when eating and MSG will give that to you and keep you coming back for more. Just like high fructose corn syrup, MSG blocks leptin and tells your body to keep on eating.
What can you do to keep from being constantly hungry? STOP EATING PROCESSED CRAP. Eat real foods that don't come from a box, chinese food restaurant, or fast food restaurant.