Unhappy in your job? It could simply be your breakfast, according to a new study, backed by leading UK dietitian

British Lion eggs dippy egg and wholegrain soldiers

Workers who start the day with sugar-laden breakfasts - think toast with jam, sugary cereals and pastries, are statistically more likely to feel low, lethargic and unfocused at work, according to new research.

A nationwide survey of 2,000 office workers drilled into the nation’s breakfast habits with some fascinating results.

Those who opt for sweet, refined-carb choices in the morning are significantly more likely to feel “shattered and lethargic” by 11am (29% vs 17% of protein eaters).

People enjoying sugar laden breakfasts were also statistically more likely to feel sluggish throughout the day (29% compared to just 19% of protein eaters).

They were also more likely to feel “unhappy” (35% vs 29%) and “unmotivated” (38% vs 32%).

According to the research, by British Lion Eggs, 21% of sugary breakfast eaters admit they regularly experience the dreaded mid morning slump, with 28% crashing out at 11am.

It’s little wonder that as many as four in ten (41%) often can’t concentrate during morning meetings. Some even resort to stealth naps at work. Over a fifth (21%) of Brits with a sweet tooth confess to having a kip on the job - in the back of their car (39%), an empty meeting room (23%) or even the office loos.

Experts say the culprit is blood sugar volatility. A sweet breakfast causes glucose to spike, then tumble, a rollercoaster the brain feels as fatigue, fog and fretfulness. Dietitian Nichola Ludlam-Raine explains: “A breakfast high in free sugars or refined carbohydrates, but low in protein and fibre, may cause blood glucose to rise and fall more rapidly. Although this doesn’t affect everyone in the same way, some people may notice a dip in energy, concentration or mood later in the morning.”

Sugar doesn’t directly cause anxiety, but fluctuations in blood glucose may produce sensations that feel similar in susceptible people. “If blood glucose falls quickly or becomes too low, the body may release hormones such as adrenaline to help restore it,” says Ludlam-Raine. “This can cause symptoms including shakiness, sweating or a racing heartbeat, which may resemble anxiety. Pairing carbohydrate with protein, fibre and healthy fats can support steadier energy and help make breakfast more satisfying.”

Protein, by contrast, is the steadying anchor. Those who prioritised protein at breakfast were more likely to report stable energy and sharper focus across the day: energetic (29% vs 19%), happy (35% vs 29%) and motivated (38% vs 32%). Protein helps slow the release of glucose into the bloodstream, blunting spikes and keeping you fuller for longer.

“Choosing a breakfast that contains protein and fibre, while keeping free sugars relatively low, can support steadier energy and help you feel fuller for longer,” adds Ludlam-Raine. “Eggs provide high-quality protein as well as choline, a nutrient involved in normal brain and nervous-system function. Some eggs, particularly omega-3-enriched varieties, also provide DHA, making them a nutritious choice before a busy morning.”

Protein conscious Brits are acting on it. Nearly a quarter (23%) track protein on apps — including four in ten (39%) 18–29 year olds and 38% of millennials (30–44) — and ideally aim to consume around 40g of protein throughout the morning.

According to those who eat a high protein breakfast, scrambled eggs come out on top (41%), followed by omelettes (28%), Greek yoghurt with nuts and berries (21%) and porridge with almonds and high protein yoghurt (15%). Other popular options include two eggs on wholegrain toast with avocado (17%), smoked salmon and scrambled eggs (14%) and the millennial classic — smashed avocado and poached eggs on toast (14%).

At the other end of the spectrum, sweet toothed Brits who can’t resist a carb heavy start go for toast with butter and jam (41%), porridge covered in honey or syrup (25%), a high sugar cereal (24%) or toast with butter and marmalade (24%). A fifth also have a preference for granola (20%), while many can’t resist a pain au chocolat (16%) or toast with chocolate or hazelnut spread (16%).

The poll also found more workers are chasing simple lifestyle changes to improve energy and wellbeing as schedules intensify, with over half (51%) saying they want to prioritise feeling more energised throughout the day. The average Briton rated their general health and fitness at six out of ten, stress and anxiety at five, and even their sex life at a moderate five.

Ludlam-Raine’s takeaway? “If you regularly experience an energy dip by 11am, it may be worth looking at your breakfast. Swapping a high-sugar option for a meal built around protein and fibre may help support steadier energy, better concentration and a more stable mood throughout the morning.”

TEN UNHAPPY BREAKFASTS, ACCORDING TO EXPERT DIETICIAN, NICHOLA LUDLAM-RAINE:

  1. Toast with butter and jam
  2. Toast with chocolate spread
  3. Porridge topped heavily with honey, syrup or jam
  4. A bowl of high-sugar, low-fibre cereal
  5. Sugary granola served without a protein source
  6. Pain au chocolat
  7. Croissant with jam
  8. Cinnamon roll
  9. Pancakes with syrup
  10. French toast topped with syrup but no fruit or protein-rich accompaniment

TEN HAPPY BREAKFASTS, ACCORDING TO EXPERT DIETICIAN, NICHOLA LUDLAM-RAINE:

  1. Vegetable omelette with wholegrain toast
  2. Dippy egg with wholegrain / sourdough and asparagus soldiers
  3. Poached eggs with spinach on a wholegrain muffin
  4. Smashed avocado and egg on wholegrain toast
  5. Greek yoghurt / kefir with berries, nuts and seeds
  6. Scrambled eggs with tomatoes and wholegrain toast
  7. Protein oats or porridge with kefir, fruit and seeds
  8. A high-protein smoothie containing Greek yoghurt / kefir, fruit and oats
  9. Overnight oats with chia seeds and peanut butter
  10. Cottage cheese with banana and pumpkin seeds