Whether you want to eat less for weight management, or reap the potential health and longevity benefits of fasting and caloric restriction, figuring out how to do so without feeling hungry or deprived is critical. Indeed, hunger is a common reason for “falling off the wagon” during weight loss, and is a risk factor for failure to maintain weight loss (see this review too). It’s also a risk factor for marital conflict — just kidding, sort of!
Enter “less is more” eating
“Less is more” is not about eating like a bird. It means choosing foods — and adopting a mindset — that allows you to feel truly satisfied with a diet that keeps your energy balance (calories) in check.
To figure out what “less is more” eating looks like for you, let’s dig into the science of satiety.
The Science of Satiety
Satiety researchers study how much we eat, when we stop eating, when we start eating again, and how we feel. Over 12,000 research papers have been published on the science of satiety in the last thirty years!
Perhaps the most profound finding from the science of satiety is that not all foods are equal in their “satiety index” — the amount of satisfaction they serve up per calorie. Two meals with identical energy content (calories) can deliver wildly different experiences. One may quench your hunger, leave you feeling pleasantly full, satisfied, and completely sated. Another may fail to make a dent in your hunger, perhaps even triggering cravings for more.
Self-experiment: Which of these one hundred calorie foods do you think would be most satisfying, and best at fighting hunger? Try them and find out!
A slice of bread. A small handful of almonds. A large apple. Three carrots. A cup of skim milk. A cup of soda or juice. A tablespoon of peanut butter. A half package of M&Ms. A scant teaspoon of olive oil. A scoop of protein powder. See more 100 calorie serving examples here.
Note: Though these foods all contain 100 calories of potential energy (calories) the actual metabolizable energy, the kind that hits your bottom line, is not the same! Learn more about When a Calorie is Not a Calorie.
Another critical finding from satiety science is that the “satiety cascade” begins even before our first bite, with the anticipation and expectations we bring to a meal.
Before we dig more deeply into the science, and how to craft a “less is more” approach, I want to be frank about some major limitations of this approach.
Limitations Of Satiety Science
Building your diet around higher satiety foods is not a quick fix to overeating. It’s just one piece of the puzzle. Today, many of us are completely disconnected from our satiety signals — it’s become normal to eat when we’re not hungry, and to eat well beyond full (bigger is better, right?!). This is no surprise given today’s “obesogenic” food environment and the pressure we may feel to look a certain way.
Disordered eating patterns present additional challenges that the science of satiety cannot begin to address. It’s beyond the scope of this article, and my expertise as a biologist (PhD in genetics), to tackle the emotional side of eating.
On a related note, none of the “rules” that I’ll be sharing are universal. We all have different physiologies (shaped by genetics, microbiome, age, health, and more) and bring different cultural and personal relationships with food to the table. These factors all influence our responses to food. Thus, you’ll need to experiment to see which strategies work for you.
With these giant caveats on the table, let’s dig into the science of satiety, and how you can use it to your advantage.
Satiety science studies two related goals for your meals: (i) satisfying you enough that you stop eating, and (ii) enabling persistent fullness that prevents you from wanting to eat again for some period of time.
- Satiation: The appetite satisfaction that develops during the course of eating and leads to meal termination.
- Satiety: The feeling of fullness after a meal, which decreases with time until it drops so low that a new meal is initiated.
The following three factors work together to shape our satiation and satiety:
- Physical fullness
- Appetite signals
- Mental expectations
Researchers test how different foods and environments influence the amount of food you consume, your appetite signals (e.g insulin, leptin, grehlin, GLP1 and CCK1) and your self-reported feelings (hunger, fullness, wanting more).
Keep reading to better understand these factors, or skip ahead to the seven ways to apply satiety science and embrace “less is more” eating.
The Big Three Satiety Drivers
1. Physical fullness
Our stomachs are equipped with sensors that tell us how full we are — literally! Signals from these distention (stretch) receptors trigger activation of various brain centers. While water alone can trigger some brain activation, the stomach to brain signals stimulated by nutrient-containing foods are far richer.
2. Appetite signals
Our hunger and satisfaction are shaped by a complex symphony of biological signals. The satiety cascade begins even before your first bite, with the thought, sight and smell of your food (hello, salivation), and unfolds as you chew and taste, digest, and absorb your food.
Satiety researchers classify the hormonal signals linking food intake to appetite as “hunger hormones”, which promote eating (e.g. grehlin) or “satiety hormones”, which inhibit eating (e.g. leptin and GLP-1). These signals can originate either in your brain, your fat cells, or your digestive tract, as described below. Your body integrates the signals from these hormones with those from your sensory neurons — such as your sweet taste buds, which are wired to light up brain reward centers.
Insulin upside? You may be surprised to see insulin listed as a “satiety signal” given its bad rap (along with all carbohydrates). In reality, insulin can be helpful in promoting satiety, though the net effect of carbohydrate containing meal depends on many other factors, including your insulin resistance and the hedonistic effects of sugar.
3. Mental expectations
Our expected response to a meal can be a self-fulfilling prophecy. If we feel that a certain meal is too small to satisfy us, then it probably will be. If we tell ourselves that “I can’t feel full without X” or “no meal is complete without X” then this will be true.
With these foundations under our belt, let’s dig in!
Seven Tips for Less is More Eating
1. Eat Your Calories: Be mindful of high-calorie drinks
The calories from our drinks (alcohol, smoothies, fancy coffees, hot chocolate) tend to pile up on top of our meals because we fail to compensate for them by eating less. This guideline does not apply to low-calorie liquids like soups, which can actually offer great satiety “value”.
Lay off the calorie-rich liquids! While the toll that liquid calories take is one of the most consistent themes in the satiety literature, we don’t fully understand why. It’s likely a combination of factors such as the lack of satiety signals from chewing and digestion, the faster ingestion rate, and the way that we equate meals with consuming solids.
2. Size Matters: Choose bulkier foods
The term “energy density” describes the calories per mass of a given food. Foods like leafy greens and non-starchy veggies (like broccoli, cauliflower, green beans, celery) have a low energy density: a heaping plateful delivers a few hundred calories at most. On the other end of the spectrum, sit high-energy density foods like olive oil, peanut butter, cheese and ice cream. A single tablespoon of peanut butter delivers the same calories as three carrots, one apple, or a huge bag of spinach.
Why turn up the volume? Serving size influences satiety through our expected satiety as well as through the stretch receptors in your stomach. Food manufacturers are actively investigating how to exploit this knowledge — such as by “inflating” foods with gas or water.
3. Dial Up the Whole Plants: Choose higher fiber foods
Most whole plant-based foods (e.g. whole grains, legumes, fruits, veggies) are loaded with dietary fiber. Animal foods don’t contain dietary fiber. Such foods are often associated with greater acute (short term) satiety.
Why dial up the plants? Higher fiber foods require more work to digest, which slows down the process and promotes more sustained satisfaction. Their bulk also contributes to your stomach’s sensation of fullness.
Note: Whole foods contain a mix of different types of dietary fibers, with complementary roles. For this reason, adding fiber to your food or drink (usually soluble fiber) will not deliver all of the health (and satiety) benefits that come from eating whole plant-based foods with intact fiber.
4. Slow Down: Chew, pause, repeat!
Your mother was right: slow down and chew your food! This strategy may not only help to decrease food intake and hunger, but helps you extract more nutrients — and more pleasure — from your food.
Chew on this! Chewing not only kicks off satiety signals, but can help you slow down enough that you register your body’s fullness signals from later down your digestive tract system before it’s too late!
5. Mind Over Matter: Know yourself, fool yourself, and challenge yourself
Our expectations can strongly shape our reality when it comes to the satisfaction we reap from our food. One of the strongest predictors of our expected satiety is portion size, which is a highly subjective measure. Use this to your advantage by switching to smaller plates and bowls (bursting with food), or simply challenge your own notion of how much food is “enough”.
Self-Experiment: A few days — or half days — of fasting, or severe calorie restriction — can be very illuminating. You may find that you can function just fine with a lot less food than you thought, when chosing wisely to maximize satiety. You may also find that you won’t actually perish from hunger!
The concept of self-fulfilling prophecy applies to your beliefs around which foods you “need” to be satisfied. I commonly hear people say that they “need” meat to feel satisfied, or that they could never be satisfied with a meal salad. Yet, when highly motivated, these “needs” can change, just like our taste buds.
While I challenge anyone to walk away hungry after one of my super-salads (think greens, beets, seeds, and smoked tofu), I don’t stand a chance against someone determined not to be satisfied.
6. Enjoy Your Food: Scratch your itches
Last but not least, don’t forget about the joy of eating! If you’ve ever felt like you still want to keep eating after a meal, despite feeling full, you know what I’m talking about. We tend not to feel sated if our meal didn’t scratch our pleasure itch. That “itch” may be related to a specific type of food or to the experience of eating.
Simply being present during your meal can make a big difference to satiety. When we eat mindlessly, we don’t take advantage of the satiety benefits that come from the full sensory experience that food provides: the smells, the taste, the sight, and the textures.
Distracted Eating. In my home, with three young children, dinnertime can be very hectic. I frequently feel that I’ve spent mealtime hastily shoving food in my face while tending to my children’s nonstop needs. It’s no wonder that I often find myself craving a peaceful “proper” meal when the kids are asleep, even though I’ve technically already eaten.
One of the best things you can do for your health is to rid yourself of the notion that healthy foods can’t be delicious. There is no reason that health and taste can’t go together. If you have an itch for a certain type of food, try to figure out the root of that itch (sweet, salty, umami, or texture), then experiment with how to scratch it in the healthiest possible way. You may find, for example, that you can satisfy your sweet tooth with fruit rather than a dessert, or a craving for salt with a cup of miso broth rather than chips.
Tips for marrying healthy & delicious? Use fresh herbs and spices liberally — they offer tons of taste, and almost no calories. * Splurge on the freshest, tastiest seasonal fruits and veggies * Head to a gourmet health-forward restaurant for inspiration * Browse instagram #healthyisdelicious * Try some of my fave dishes, like cauliflower steak and Turkish white bean salad with dill. * Keep experimenting until you find your winners.
7. Know Your Triggers: Proceed with caution
The other side of the pleasure coin is that we need to be aware, and mindful, of our trigger foods — the ones that cause us to crave more, and overeat. It can be challenging to balance indulging ourselves in “treats” while not setting ourselves up for counterproductive outcomes. Some people find that black-and-white rules work best, while others respond poorly to such restrictions. I wish I had a simple answer!
Macronutrient Confusion (Carbs, Fats, Proteins)
Those of you who follow the field of nutrition may be surprised that I didn’t include macronutrients (proteins, fats, and carbohydrates) on my “A list”.
While it’s often reported that “protein is the most satiating nutrient” (followed by carbs, then fats) the scientific evidence for this satiety hierarchy is surprisingly weak, and highly inconsistent. For every trial that shows a benefit of dialing up (or down) a certain nutrient, there is at least one more than does not show this benefit. My favourite review on macronutrients and satiety concluded:
“At this point the predictive power of the macronutrients for energy intake remains limited.” Carreiro et al, 2016
In fact, many of the satiety differences that we attribute to macronutrients can be largely explained by the mechanisms above. For example, many high-fat foods like olive oil, peanut butter and ice cream are high in energy density (see Tip 2) and low in fiber (see Tip 3). Similarly, lower carbohydrate diets can help prevent overeating because they keep you away from “eat more” triggers that counteract the satiety value of the food (Tip 7). Thus, following my seven steps to satiety should cover your bases.
The Bottom Line
Dial up your high-satiety foods; be mindful of low-satiety foods and trigger foods; and scratch your pleasure itches in healthy ways. The principles are simple, but leave a lot of room for interpretation. To build your “less is more” lifetime diet, you need to tailor them to you — your physical, mental, and emotional response to food .
Last but not least, comes the elephant in the room. Satiety-boosting strategies are only as powerful as your connection to your satiety signals. Boosting your satiety does not guarantee less food intake. Indeed, studies commonly find discrepancies between self-reported satiety and food intake (e.g. fiber-rich pulses, chewing). While there is no simple recipe for rebuilding your satiety connection, my hope is that the simple act of tuning into your satiety signals is a step in the right direction.
As a refresher, here are seven strategies to help you feel good while keeping calories in check:
- Eat Your Calories: Be mindful of high-calorie drinks
- Size Matters: Choose bulkier foods
- Dial Up the Whole Plants: Choose higher fiber foods
- Slow Down: Chew, pause, repeat
- Mind Over Matter: Know yourself, fool yourself, and challenge yourself
- Enjoy Your Food: Scratch your itches
- Know Your Triggers: Proceed with caution
I would love to hear how these strategies work for you!