Do we make good decisions after a meal? Some food for thought, literally!

Imagine you’ve had the most epic food. You are now satisfied. But you have to get back to work and make decisions. Will they be safe decisions? Risky decisions? Wrong decisions? Perfect decisions? Would you’ve chosen differently on an empty stomach? Behavioral economics and psychology have some answers.

A good meal can aid important decisions but also make us risky, while hunger can make us choose safe and easy options. But it's not so simple. Share on X

We have hot and cold states that modify our preferences

The physical state of our body affects our decision-making. For example, feeling hungry, satiated, thirsty, or full in a food coma affects how we choose between options. These bodily states are either “Hot states” or “Cold states.” Hunger and thirst are hot states, while satisfaction after food and fatigue without food are cold states. Hot states typically make us impulsive, rely on emotions and gutfeel, and seek immediate gratification, while cold states don’t. For example, sexual arousal (hot state) can increase risky sexual decisions. Hunger can increase the urge for food in a way that ignores health goals. These are domain-specific decisions – feelings about XYZ affect decisions about XYZ. However, hot states also affect general decisions in a more nuanced way.

Hunger (and thirst) indicates that our biological resources such as glucose and nutrients are depleted. This deficient state affects our thinking process because the brain needs those resources. Let’s see what the effects are.

1. Hunger makes us less risky and more careful

Small increases^[1] in hunger induced by advertisements likely reduce real-world risk-taking behavior (as seen in gambling decisions). The effect is more prominent in people who generally take more risks. Assuming the study holds up against replication, it means that being hungry reduces risk-taking in uncertain situations and risk-taking people are likely to be less risky when hungry.

Hot states don’t necessarily lead to bad risky decisions. In some cases, they promote strategic thinking^[2] about risky decisions. People may become more calculative when hungry when their decisions have uncertain outcomes. So, being satiated might make one deal with risky decisions more casually or sub-optimally. For example, while making purchase decisions you know nothing about, a hungry state might motivate you to take a chance on a new product on amazon with no reviews. But you might also google for more reviews and seek general information to see if it is legit or not.

When our options are rewarding, we tend to be risk-averse when the risks or cons are explicitly mentioned. But we become risk-taking when there is no explicit description of the risk, but we’ve learned about the risks through experience and developed a judgment. Hunger might reduce risky decision-making^[3] when we are supposed to choose between options with no clear pros and cons, but we have sufficient experience in anticipating the risks. For example, we may have the option to choose between Amazon.com or a cheaper unknown e-commerce site for a risky purchase. One concern is if the unknown site is a scam or not. If you are an experienced online consumer, hunger may bias you against the unknown site.

Risky people turn safer, and safer people turn risky when hungry

In some cases, people are more ok with taking risks when hungry. But a person’s baseline risk-taking tendencies affect if they make risky or safe decisions. Data suggests^[4] those who are generally risk-averse (safer) after eating become more risk-seeking, and those who are risk-seeking become relatively risk-averse (safer) on an empty stomach.

A popular but unreliable idea shared across media is that hunger and a craving for food makes people less sensitive to risky information. So hunger increases risky decision-making. The famous^[5] study failed replication^[6], and the opposite trend – hunger reduces risk-taking is emerging.

2. We may take more risks up to an hour after a meal

Hormones ghrelin and leptin are involved in our sense of hunger or being full. Ghrelin increases appetite, and leptin decreases it. Researchers measured these and saw people’s preference for risk. When we are low on energy supply, like in a fasted state, we tend to make relatively safer decisions than when we are full. Once we eat, risk-taking increases^[7] for an hour after a meal, after which we enter a neutral zone of decision-making unrelated to hunger (while ghrelin is low). Many financial and business decisions are made after a meal – the seller wants the buyer to take risks, so the seller feeds the buyer to increase their risk-taking appetite right after lunch.

3. Food affects emotions, and emotions affect decisions

An empty stomach makes many of us cranky, which can affect other decisions. Similarly, after a meal, when we are satisfied, we feel great (unless it’s a food coma), and those positive emotions affect decisions. Crankiness might make us bitter about any option we get next. Suppose you are in a bad mood from low glucose at work and have to accept 1 of 2 versions of a sentence used for marketing. Those negative emotions might make you dislike both options. This “affective priming^[8]” is more likely when you are not too conscious of your bad mood and hasn’t turned into a full-fledged mental state.

Restrained eating^[9], like having a calorie deficit or following a diet you aren’t used to, can induce hunger, stress, and negative emotions like sadness and loneliness. Even hunger cravings can induce similar feelings along with boredom. Generally, boredom is a direct foundation for making risky or stimulating decisions. 

Hangry (hungry + angry)^[10] is a real hybrid emotion where hunger leads to anger and irritability. In such states, people make decisions that repair their moods. Procrastination is one example of it. A large part of emotional regulation is choosing behaviors that tame extreme emotions.

Emotions affect consumer decisions. In a series of experiments^[11], students in a positive mood were less prone to marketing tactics than students in a negative mood and chose products that were average or balanced across all features. If hunger makes you hangry or sad, you may be more susceptible to marketing. And if you are satisfied after a meal, you may make a good enough decision.

Positive emotions^[12], which often come from a good meal, create facilitative feelings like wanting to put the effort and energy into exploring and fantasy feelings like imagining how great it would be after a decision. This effect is enhanced when a purchase decision appeals to one’s identity. For example, after a good meal, you may want to buy clothes that speak to your personality and fantasize about how great you would look. However, it is partly wishful thinking, which comes with overlooking the negatives of a decision.

Positive emotions broaden one’s perspective and take focus away from details. Similarly, negative emotions narrow our perspective, and our decisions might be based more on finer details. This is the broaden-and-build theory.^[13] In short, when full, positive emotions increase, and our choices are based on liking or disliking the broad features (we like the general idea). When hungry, negative emotions increase, and our choices are based on liking or disliking the finer details (we nitpick). For example, hunger may demotivate you to go to Hawaii because you hate the idea of swimming which you fixate on. But after a meal, you may love the idea of a trip to Hawaii but not worry about swimming because you consider all the other options for enjoyment.

Food makes us feel safe, which usually increases our risk-taking appetite. Hunger makes us feel unsafe, which usually decreases our risk-taking appetite. Share on X

4. Being full or hungry affects our preferences, but we underestimate its influence

There is a secondary problem that emerges from having hot and cold states while making decisions – the hot-cold empathy gap. The hot-cold empathy gap^[14] states that we don’t acknowledge the influence of hot states like hunger and cold states like being full on our preferences/decisions. Moreover, we overestimate how stable our preferences/decisions are in both states, which often differ during neutral states. For example, one might say they love classical music during a cold state, like drowsiness after a good meal. However, they may conclude they love rock music during a hot state. But during the hot or cold state, they might overestimate their preferences, saying, “I’m a huge classical fan, I listen to it so much,” when, in fact, they are typically a pop-listener during neutral states.

There is another layer to the hot-cold empathy gap – a social context. We find it harder to relate to someone in a neutral or cold state when we are in a hot state. If the emotional state of 2 people isn’t the same, we find it harder to relate. And we also discount the impact these states have on our and others’ decisions. For example, we may make bad decisions about a relationship when a partner or a friend is in a different hot state due to stress from a major life event. You may conclude that they made decisions that don’t favor you because of some other problem in the relationship, but in reality, that decision may come from the hot state of anger or frustration from that life event.

5. Hunger might make us think less and make pointless decisions

Psychologists describe hunger and thirst as a “need state,” where the body needs something and wants to re-establish homeostasis (a balance of all internal functions). However, the brain is limited in finding the most accurate way to reach homeostasis due to errors in decision-making. Our “interoceptive sense” – the sense to understand bodily signals – is not typically precise, so we mistake one feeling for another. For example, being thirsty might lead to misinterpreting thirst where one decides they need food and not water, according to a study performed on mice^[15]. The worst-case implication is that having a need state might lead to decisions that have nothing to do with the need state and make us choose something else. For example, hunger might make you buy an OTT subscription, or feeling thirsty might make you want to call a friend saying you are feeling “hollow” and “unsatisfied” with something.

Work can make us hungry because the brain uses glucose. This makes us tired. Research has demonstrated that we resort to intuitive simplified decisions^[16], reduce effort^[17], and avoid ambiguity^[18] during a mentally and physically depleted state. One study^[19] looked at how judges make decisions in the real world and found that adhering to the law with a deliberate, analytical approach isn’t enough to explain their decisions. They found that having or skipping food can change their ruling. The current explanation is that we resort to decisions we are used to making when our biological resources are low. So judges who often ruled harshly would resort to ruling harshly, and those who ruled leniently would rule leniently.

Some decisions are beyond purchases or productivity – these are the moral decisions about harm, justice, and tolerance for others’ behavior. It turns out hunger affects those, too – by creating a “gut feel.” In a study^[20] that looked at intuitive and logical thinking in the presence of hunger and thirst, researchers found that those who tend to be intuitive are less repelled by the idea of causing harm to others. They explain this with attention going inward toward their own hunger/thirst (the actual gut feel), which interferes with deliberate thinking, without which they could’ve chosen the opposite moral decision – it’s best to avoid harming others. Some insight comes from animals; in this case, a worm called C. elegans. Researchers observed^[21] that food deprivation made the worm more willing to cross a barrier that could harm its body. In effect, hunger increased threat tolerance. This has implications for political decisions – your final gut instinct to vote for someone or judge an influencer for their thoughts might depend partly on how hungry you are. Essentially, you may even reverse your preferences based on how full or hungry you are.

We resort to intuitive simplified decisions, reduce effort, and avoid ambiguity during a mentally and physically depleted state. So hunger creates automatic, familiar decisions, and food creates effortful decisions. Share on X

6. Hunger makes us weak at seeing the future value of decisions

Ideally, important decisions, which need rational thinking and proper evaluations, should be made after a meal. When hungry, we desire instant food instead of waiting a few hours for a good meal. This is an example of a tendency called “delay discounting^[22],” which says we sometimes prefer small but quick gains and devalue larger gains in the future. High delay discounting means we fail to see the value of long-term gains in the future for one option and then choose instant gratification. Considering that important decisions, especially those about health, career, relationships, and finances, all have rewards in the future, it’s best not to use delay discounting.

Unfortunately, hunger induces delay discounting in food, and it also spills over at about 25% intensity to other areas of decision-making, according to a study.^[23] Participants in the study were willing to wait only for 3 days for double the reward when hungry but 35 days when they weren’t hungry. For example, if you are hungry, you might impulsively follow up on an email in an annoying way instead of waiting for a few days for a reply. Suppose a phone you like isn’t available today but will be in a week. If you are hungry, you may buy a cheap alternative available today instead of the desired one a week later.

Core motivations affect if we approach or avoid a decision

A crude but simple way to look at how hunger and thirst affect decisions is by looking at our core motivations from an evolutionary perspective^[24]. Thirst and hunger increase the motivation to seek food and water. This motivation to approach resources is called approach motivation. Similarly, states like fear or disgust motivate us to run away, which is called avoidance motivation. So when our approach motivation is triggered, we might decide and act to acquire something. And when avoidance motivation is triggered, we might make decisions to avoid something.

Approach/avoidance motivation^[25] is a general readiness to act, and then we develop specific goals to act on that motivation but sometimes forget it’s about thirst or hunger. These goals could be making purchases, finishing a report right away, procrastinating, going on a date, doing a health check-up, etc., loosely aligned with the motivation.

If our approach motivation for food is very high through a drop in blood glucose, we might make^[26] any risky decision that takes us to food faster. And the decisions between now and food are optimized to reach food. So, when with friends, if you are offered to watch a movie you are very excited about and then eat, or eat first and then watch it, you are likely to choose the second option when hungry and delay the movie.

Our relationship with food also affects decision-making indirectly. Overweight teenagers exhibited more risky decision-making after hunger induced by exposure to food cues in one study^[27]. The risky decision-making can itself lead to more overeating, causing an obesity problem. This behavior is closely related to sensation-seeking, a desire to seek immediate stimulation. Food cues through ads, images, conversations, smells, etc., would make one riskier if they have an unhealthy relationship with food.

Takeaway

Perhaps it’s best to first think if you are hungry or thirsty to evaluate how it’s influencing your thought process, and then have a meal and re-think your preferences. This takeaway is a very safe takeaway because I am hungry.

Note: Marketers and advertisers can use these insights on how people make decisions after or before food to improve messaging and sales strategies.

Sources