Festive excesses push many of us towards a new year diet but for Mr Rob Hobson, nutrition consultant and author of The Detox Kitchen Bible, there isn’t a one-size-fits-all solution to weight loss. “My preferred approach is to make small changes,” he says, putting the emphasis on diet quality as well as smaller portion sizes. “Simple food swaps, cutting right back on the booze and getting rid of unhealthy snacks always seems to get good results. This way of eating also helps instil behavioural changes that are long term.”

He recommends switching sugary breakfast cereals for high-protein alternatives such as boiled eggs or low-fat Greek yoghurt topped with berries and crushed nuts. Ditch creamy sauces for those that are tomato or stock-based and opt for wholegrain pasta, bread and rice (while also eating less of these foods in favour of lean proteins, healthy fats and vegetables). Foods with a high water content such as soups, stews or tagines can also help to keep you feeling full on fewer calories.

“Some find it easier to stick to their weight loss plan if they allow themselves a ‘free’ day when they can eat what they like. It may take a little longer to lose weight but if it helps you stick to your long-term goal then so be it,” he says. “The only diet that works is the one you know you can stick to.”

For those seeking to supercharge their workout, diet can play a big role in bulking up. “The bottom line is that you’ll need to eat more food, which means extra meals during the day alongside healthy snacks,” says Hobson, adding that the basic rules of healthy eating still apply. “Lots of men take the wrong approach of guzzling down protein shakes and eating foods high in sugar and bad fats, which isn’t great for your health.”

Instead, Hobson recommends eating a source of protein with every meal and getting even more into your body after training. “Protein shakes can be useful and you can bulk them out with other ingredients such as avocado, nuts butters, coconut oil, nuts, seeds, bananas and berries to help you to gain weight,” he says. “Carbs are just as important for weight gain so include plenty of wholegrain versions of pasta, rice and other grains as well as foods like jacket and sweet potatoes.”

He adds that in certain situations, supplements such as creatine can help, too. “This helps with bursts of short-term, high-intensity exercise to support increased muscle mass and strength,” he says, advising an initial loading phase, or intake, of 20g per day for a week followed by a lower dose of 5g a day.

While the come-to-bed effectiveness of aphrodisiacs is up for debate, sex counsellor and psychotherapist Dr Ian Kerner says nutrition does impact our sexual health. “Sexual self-esteem is tied into body image, so it’s important to eat in a way that allows you to realistically maintain the weight that contributes to your sense of sexiness,” he says, adding that throughout Covid he’s seen numerous patients ignore their diet, gain weight and lose interest in sex. “A healthy diet provides both psychological and physical benefits to one’s sex life – confidence and sexual self-esteem are an arousal-oriented infrastructure.”

Given that blood flow lies at the heart of sexual health, he recommends foods focused on heart health. “In men, the arteries and capillaries going into the genitals are among the thinnest in the body, so when they start to get blocked it can lead to erectile impairment – we want to keep that blood flowing,” he says, adding that enriching your diet with nuts and seeds which contain circulation boosting L-arginine, as well as fruits such as apples and strawberries that are high in flavonoids – known to promote lower blood pressure. “Oysters are considered an aphrodisiac because they contain zinc, which is known to help with circulation, but look for other foods such as some seeds and meats that also contain zinc,” he says. “Elsewhere, salmon is known to be rich in omega-3 fatty acids, which have numerous benefits such as lowering triglycerides.”

Nutrition and sleep aren’t always the best bedfellows, says Dr Guy Meadows, sleep expert and founder of London-based Sleep School, adding that too many of us consume the wrong thing – sugar, caffeine or alcohol – too close to our bedtime, which can cause sleep disturbance. “The problem is that nutrition is a very active process – it increases our metabolism, which increases body temperature, which is the very opposite of what should happen when we sleep,” he says, adding that this can affect the quality of our sleep and see more food stored as fat. He recommends ensuring that our evening meal is the lightest and healthiest, and leaving between two and four hours between eating and sleeping.

“The internet can point us in the direction of thousands of so-called ‘sleepy foods’,” he says, listing cherry juice, almonds and pumpkin seeds as just three examples. “But we run the risk of obsessing over these specific components, which can mean the solution then becomes part of the problem.” Instead, he advises eating a balanced, Mediterranean-style diet – larger portions of fibre, fruit and vegetables, natural starchy carbohydrates and smaller portions of white meat, fish and unsaturated fats – which is proven to boost sleep quality and sleep satisfaction.

Bring your A-game to the boardroom by starting the day right. “The majority of research suggests that breakfast boosts energy stores, enhances brain power, concentration and even mood, yet over a third of us regularly miss this meal,” says Harley Street nutritionist and corporate wellness specialist Ms Lily Soutter, who recommends porridge, eggs on wholegrain toast or a low-sugar cereal with fresh fruit and natural yoghurt. “Eating a breakfast containing some starchy carbohydrates can help to provide our body and brain with a steady supply of energy throughout the morning.”

Further easy fixes to keep firing throughout the day include keeping hydrated – Soutter explains that even mild dehydration can reduce short-term memory and impact cognition test scores – and getting off what she calls the “blood-sugar rollercoaster”.

“While it may be tempting to rely on high-sugar snacks to improve alertness, many options can result in blood-sugar highs and lows,” she says. “Low blood sugar can lead to energy slumps, lack of concentration, irritability and may stimulate further cravings for sugary ‘quick fix’ foods.” Instead, choose snacks that combine protein, fibre and a little healthy fat to slow the rate at which sugar is released into the bloodstream.