Nutrition expert Robbie Puddick recommends eating more fruit and nuts for weight loss during the summer. He warns against fad diets and suggests healthier substitutes like fruits and nuts for snacking. These foods provide essential nutrients and can help with sustainable weight loss. Opting for fruit and vegetables as part of daily intake is advised by the NHS, while unsalted nuts are a good choice for snacks, as per the British Heart Foundation. Puddick emphasises the importance of a long-term, healthy approach to weight loss rather than quick fixes promoted by social media trends.