1. Do: make a tough decision.
You’re likelier to make smarter choices on an empty stomach, recent Dutch research found. According to Men’s Health, “Study participants who fasted before taking a series of tests made winning choices 50 percent of the time, compared with only 40 percent of the time for folks who ate a meal beforehand.” Study author Denise de Ridder, PhD, told the magazine: “Being hungry may make you think less and act more on impulse.” Unlocking your intuitive thinking might help you make the right decision.
2. Do: get intimate.
Cozying up after date night—if it includes an indulgent meal—might be the exact wrong time, according to MedicalDaily. Digestion requires a lot of the body’s energy resources, which can reduce blood flow crucial for an erection. Feeling bloated or sluggish can dampen women’s libidos as well.
3. Don’t: go shopping.
You’ve heard not to hit the grocery store while hungry, but feeling ravenous during any kind of shopping might not be the best move for your wallet. In a recent study, researchers looked at the receipts of 81 people exiting a department store; the customers also rated their hunger and mood. Those who were hungrier than average spend 64 percent more money than those who were less hungry, even after researchers accounted for such factors as mood and time spent shopping.
According to New Scientist, the hormone ghrelin, which is released when we’re hungry, also affects an area of the brain called the ventromedial prefrontal cortex, which is involved in reward and motivation. A study author told the magazine, “If [consumers] go shopping on an empty stomach, they might spend more than they intend to – so better to feed themselves before they go out.”
4. Don’t: bicker with your partner.
If you’re feeling peckish, eat something before you lash out without meaning to. In a study published last year, Ohio State University psychology researchers studied about 100 married couples for three weeks. Each night they tested their blood sugar levels and asked each participant to stick pins in a voodoo doll that represented their spouse. People with the lowest blood sugar pushed twice as many pins into the doll as those with the highest levels. “Self-control takes a lot of fuel,” says Brad J. Bushman, PhD, an anger researcher, told The Good Life, Dr. Oz’s magazine. “Our brain is fuelled by calories, including the prefrontal cortex that controls reasoning and emotional control. The brain uses about 25 percent of calories we take in.”
5. Don’t: hit the gym.
Some people think that exercising on an empty stomach burns more fat (because instead of burning carbs you’ve recently eaten, the body will use fat stores for fuel), but research shows this isn’t the case. A report published a few years ago in Strength and Conditioning Journal found that you burn the same amount of fat regardless of whether you eat before working out, but you are more likely to lose muscle mass when you (literally) run on empty. What’s more, exercise intensity and overall calorie burn is less.