When it comes to my body, the idea is straightforward: view it as a car.
For a car to go far, I need to put fuel in it—and similarly, the food I give my body translates into the energy that carries me throughout the day. Not eating well is like putting water in a car tank: it feels and looks full, but I won’t go far.
And for the car to last, I need to bring it in for maintenance. My car then comes back as good as new.
Similarly, the care I provide for my body—such as intellectual stimulation for my brain, exercise, or massages—keeps it functioning well.

So it boils down to two questions:
1. What do I feed my body with?
2. How do I maintain my body?

The benefits are twofold: I’ll feel stronger and more energized every day, and I’ll age better. 
Both the short term and the long term are linked when it comes to my body: how I age is the consequence of how I act today, and how I act today directly impacts my energy levels throughout the day.

To start feeding and maintaining my body better, let’s refer to science. 

Below are a few good principles to keep in mind and apply concretely.

And to be clear: none of this is meant to make me feel guilty. 
Rather, it is about making me aware so I can make my own choices. Also, we are all human: sometimes, I will eat the “wrong” thing, and that’s OK too—provided I am not excessive with it.

1. Sugar creates addiction—that is precisely why I find it in most manufactured foods. It keeps me coming back for more.
Be mindful of this ingredient: science shows that sugar activates my brain in a way that triggers cravings for more. Specifically, sugar causes a rapid release of dopamine, a neurotransmitter associated with pleasure and reward. This creates a cycle of craving sugar to sustain the pleasurable effect, much like addictive substances.
The effect is especially visible in kids, who can have mood swings or find it hard to stop eating sweets. As adults, we may feel more in control, but the signs are still there.
Sugar is king at fooling me: it feels like I love it, but my body—including my brain as an organ—does not. The more I eat sugar, the more prone I become to illnesses over time, such as obesity or diabetes.
Interestingly, everyone who tries reducing sugar notices the difference over time: as I cut back, I’ll start tasting how sweet things actually taste. What I once enjoyed now feels too sweet! Reducing sugar is a game-changer, as I will experience it myself.

2. Cooking for myself is always better. If my schedule doesn’t allow it, even a few times a week is good. I could also cook in the evening for the next day, or batch-cook and freeze meals for busy times.
Cooking has many benefits:
I know exactly what ingredients I’m using and will typically avoid adding sugar, unlike store-bought foods.
I will value and enjoy my meals more because I’ve prepared them myself.
Cooking can be as enjoyable as doing crafts as a child. Looking up recipes and assembling ingredients can be a fun process.
It doesn’t have to take hours nor be complicated. Simple options include cutting raw vegetables for a salad, blending cooked veggies into a soup, or grilling good meat or fish with a green salad on the side.
Plus I tend to eat more vegetables when I cook, which is a healthy habit to cultivate.
3. A little of everything is a good habit. That is no science: that is common sense. Try to vary my diet so my body gets energy from different sources. This approach also allows me to enjoy anything I like, with moderation. For example, eating fries occasionally is fine, but having them daily is not!

4. Avoid gluten and proteins together to ease digestion. Overall, digestion uses about 10% of my body’s energy, but processing proteins can take up to 25% (look up “thermic effect of food (TEF)” for more information).The energy my body expends on digestion depends on both the quantity and type of food consumed.
When possible, avoid combining pasta with meat; instead, pair meat with vegetables. Gluten and protein are the most demanding to digest, so keeping them separate helps conserve energy for other activities.

5. Focus on fruits and vegetables as the main source of energy. The majority of what nourishes my body comes from these. The general recommendation for daily nutrition is that half of my plate at each meal should consist of fruits and vegetables. Rationale behind is that they provide essential nutrients like vitamins, minerals, antioxidants, and dietary fiber while being low in calories. Fruits and veggies reinforce my overall health, help prevent chronic diseases, and improve digestion.
Accordingly, when I shop at the supermarket, the fruits and vegetables section is where I should stop and buy the most.

6. Eat when my body is hungry, not when my brain wants comfort food. Meaning before eating, I should ask myself if my body is genuinely hungry or if it is my brain seeking comfort.
On the other hand, if I haven’t eaten recently, I should check if my body needs food. The key is to let my body, not my brain, lead the decision.

7. Drink water throughout the day. The easiest way to ensure I drink enough is to start the day with a full 1-liter bottle on my desk.
Human bodies are composed of 50–70% water, depending on age and gender. About 20–30% of daily water intake comes from food (if I eat enough fruits and vegetables). The rest must come from drinking. This means 1.5 liters daily for women and 2 liters for men - usually much more than we think to drink.
Dehydration affects my skin, organs, and overall health. For example, it can cause headaches, lack of concentration, kidney malfunction, increased stroke risk, and cramps. 
So, I must ensure I drink enough water.

8. Do sports—or more broadly, move my body. 
Beyond the immediate benefits to my health and mood, regular physical activity allows me to release pent-up energy and vent physically. Studies also show that people who engage in regular exercise tend to age well and longer. 
Our bodies are not designed to remain seated all day: it’s important to give it a break by moving daily. This doesn’t have to be complicated—it could be as simple as stretching or taking a run around the block. It also doesn’t need to take long: 30 minutes of movement a day is sufficient. Accordingly, I should still take every opportunity to move. Small actions count, such as walking reasonable distances or choosing stairs over the elevator.

9. Treat myself. I need to make time to enjoy and care for my body by indulging in relaxing activities, for instance spending time in a hammam or sauna, getting massages, enjoying a haircut, or treating myself to a skincare session. It’s essential to appreciate my body—not just as a vehicle for achieving goals but as a source of pleasure and comfort. To come back to the car metaphor: in addition to commutes, why not enjoy the ride too?!

To state the obvious: as long as my body lasts, I’m alive! So, let's act as a good parent and take good care of it!
It is not about becoming overly controlling about my body. What matters is to be directionally correct with a balanced diet and some physical activities.