An Observational Perspective on Christmas Eating, Fatigue, and Seasonal Weight Gain

The Christmas and holiday period is often framed as a time of rest, indulgence, and recovery from a demanding year. Yet clinically, it is one of the most common times when people report feeling more bloated, more fatigued, less motivated, and less comfortable in their bodies.

This experience is frequently explained as “needing a break” or “finally catching up on sleep.” However, when behavioural patterns are assessed rather than intention, physiology suggests a different explanation.

For most people, feeling worse over the holidays is not a sign that the body required excess. It is a predictable response to disrupted habits during an unstructured period of time.

Seasonal Weight Gain: What the Data Shows

Population-based research consistently demonstrates that the average adult gains approximately 0.4–1.0 kg over the Christmas and holiday period. Importantly, longitudinal data shows that this weight is rarely lost in the months that follow, instead accumulating gradually year after year.

This weight gain does not occur from a single day of eating. It reflects several weeks of compounded behavioural changes, including increased energy intake, reduced physical activity, higher alcohol consumption, disrupted sleep, and irregular meal timing.

From a clinical perspective, this is not a failure of willpower. It is a predictable metabolic response to loss of structure.

Why “It’s Just One Day” Rarely Holds True

In practice, Christmas is almost never one isolated event. It often begins weeks before Christmas Day and extends well into January.

During this period, routines loosen. Meals occur later and less consistently. Snacking frequency increases. Alcohol intake rises. Bedtimes shift later. Morning movement becomes less frequent.

Each of these changes independently affects appetite regulation, insulin sensitivity, circadian rhythm, and energy levels. When combined, they create a physiological environment that promotes fatigue, bloating, fluid retention, and fat storage.

This is why many people feel uncomfortable not just after Christmas Day, but throughout the entire festive period.

The Physiology Behind Holiday Fatigue

A common experience during time off is feeling more tired despite sleeping more. This is often interpreted as evidence that the body “needed rest.” However, physiologically, fatigue during the holidays is more strongly associated with behavioural inputs than recovery.

Later nights and inconsistent sleep timing disrupt circadian rhythm. Alcohol fragments sleep architecture and suppresses REM sleep. Late or prolonged eating windows interfere with glucose regulation and digestive rhythm. Reduced daily movement decreases insulin sensitivity and lymphatic circulation.

Even when total sleep duration increases, sleep quality often declines.

The result is persistent tiredness, brain fog, low motivation, and a sense of heaviness that can make it harder to enjoy time off rather than easier.

Unstructured Time and Appetite Dysregulation

Structure plays a key role in appetite regulation. When structure is removed, hunger and fullness cues become less reliable.

People often eat because food is available, social, or emotionally linked to rest and reward rather than physiological hunger. This commonly leads to eating beyond satiety, abdominal distension, reflux, and digestive discomfort.

Importantly, this pattern rarely enhances enjoyment. Instead, it overrides normal feedback mechanisms.

How Did We Get Here? Overfeeding as a Cultural Norm

To understand why festive discomfort has become normalised, it is helpful to examine the broader cultural context.

For most of human history, food availability was inconsistent and effort-based. The human nervous system evolved to prioritise energy storage during periods of abundance. Sweet and fatty foods were rare and highly reinforcing.

In modern environments, those same foods are constantly available, highly palatable, and engineered to override satiety signalling. During the festive season, this is amplified further by social expectation, tradition, and emotional meaning.

Overeating has become symbolic of rest, reward, generosity, and togetherness.

For many people, Christmas represents permission to finally let go after a year of stress, productivity, or restriction. Excess is not just about food. It is about relief.

However, when relief takes the form of complete behavioural abandonment, the body absorbs the cost.

The Role of Restriction and Diet Culture

Chronic dieting and prolonged restriction also contribute to festive overconsumption. When food intake is tightly controlled for much of the year, periods of perceived freedom often trigger rebound eating.

This is not a lack of self-control. It is a predictable physiological and psychological response to restraint.

The festive season becomes the release valve.

Over time, this reinforces the belief that excess is inevitable, rather than prompting reflection on why so many people enter December already depleted, dysregulated, or metabolically unstable.

Social Normalisation of Discomfort

Another contributing factor is social reinforcement. Feeling overly full, bloated, or exhausted is often framed as humorous or expected during celebrations.

When discomfort is shared collectively, it becomes normalised. Over time, people stop questioning whether it is actually necessary.

From a physiological standpoint, repeated digestive distress, poor sleep, and metabolic disruption are signals worth responding to, not experiences to dismiss.

Overfeeding Does Not Equal Nourishment

One of the most important clinical distinctions is that eating more does not necessarily mean nourishing the body.

Overfeeding in the absence of adequate protein, fibre, micronutrients, and regular meal timing often leads to poorer glycaemic control, increased inflammation, disrupted digestion, and reduced energy.

The body does not respond to single meals, it responds to patterns!!

When patterns signal chaos, the body compensates accordingly.

Why Preparation Matters More Than Restriction

Each year, I run a group leading into the Christmas period. The intention is not restriction, but preparation.

Women who enter December with stable routines, regulated blood sugar, consistent protein intake, adequate sleep, and supportive habits consistently report feeling better during the festive season, not worse.

This year, women in my groups are heading into Christmas having lost between 2 and 15 kg. More importantly, they report reduced fatigue, less bloating, greater confidence around food, and no sense of needing to reset in January.

They still enjoy traditional foods. But those foods are integrated into a body that is regulated, not depleted.

Reframing Rest and Recovery

True recovery does not come from abandoning structure entirely. Physiologically, rest is supported by regular sleep timing, stable meal patterns, adequate nutrient intake, gentle daily movement, and moderated alcohol exposure.

When these foundations are removed, the body does not rest, but instead it  compensates.

This compensation is often misinterpreted as needing more sleep, more food, or more indulgence, when in reality it reflects behavioural disruption.

Overall, enjoyment and health are not opposing concepts. Neither are celebration and self-regulation.

Feeling sluggish, uncomfortable, and disconnected during time off is not inevitable. It is largely behavioural and therefore modifiable.

When we understand how sleep, alcohol, meal timing, and routine influence physiology, we can make choices that allow us to genuinely enjoy time off rather than recover from it.

Lastly. Education, Not Willpower: Understanding Food Addiction and Eating Behaviours

One of the most important shifts in supporting long-term change around food is moving away from willpower-based thinking and toward education.

Overeating patterns, binge eating, and loss of control around food are rarely about a lack of discipline. They are influenced by neurobiology, dopamine signalling, stress physiology, habit formation, emotional regulation, and learned behavioural responses.

This is why education matters.

I have created an in-depth lecture on overcoming food addiction and dysregulated eating behaviours, which explores:

• Why certain foods drive compulsive eating patterns

• How stress, sleep deprivation, and restriction amplify cravings

• The role of dopamine, reward pathways, and emotional relief

• Why awareness and structure are more effective than avoidance

• How to rebuild trust with hunger and fullness cues

You can access that lecture here:
https://www.loom.com/share/10808e8a50db4382806b6aced9df2c5f?sid=eb1b55e4-1807-41fa-bfe1-8bc753442e26 

This type of education is available to all of my 1:1 clients, alongside over 40 recorded educational videos designed to upskill, empower, and support long-term behaviour change.

The goal is not compliance. It is understanding.

When people understand why they eat the way they do, patterns become easier to interrupt, especially during high-risk periods such as the festive season.

*** If you’re interested in 1:1 coaching and personalised support through the festive season and beyond, you can learn more about my programs and memberships here: https://www.inherhealthclinic.com/memberships

References

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5. Broussard JL, Van Cauter E. Disturbances of sleep and circadian rhythms and metabolic consequences. Endocrine Reviews. 2016;37(6):584-608.

6. Chaput JP, et al. Short sleep duration increases energy intake but does not change energy expenditure in adults. American Journal of Clinical Nutrition. 2013;98(2):410-416.

7. Heianza Y, et al. Role of eating timing in weight regulation. Current Obesity Reports. 2019;8(2):190-199.

8. St-Onge MP, et al. Meal timing and frequency: implications for metabolic health. Circulation. 2017;135(9):e96-e121.

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