Jackson like to keep a mix of different nuts and seeds in a container, which she sprinkles on meals like salad and oatmeal.This provides a good source of healthy fats but also diversity which the gut microbiota love, she said. Whole grain carbohydrates, such as brown rice, wholemeal bread, wholemeal pasta, oats, and quinoa are staples in Jackson's kitchen.They all cook really quickly and form an awesome base for your main meals, she said. Jackson eats a variety of vegetables because she's signed up to a delivery service that sends her boxes of in-season vegetables or those that might have been thrown away.Eating a wide variety of vegetables can help reduce the risk of heart disease, stroke, and certain cancers, lower a person's blood pressure, and improve digestive issues, Insider's Savanna Swain-Wilson previously reported. Frozen fruit is cheaper than fresh, and it also contains more micro-nutrients as it's frozen soon after picking, Jackson said.Jackson keeps two types of olive oil in her kitchen:High quality virgin olive oil: It's amazing for its antioxidants and making things like hummus or drizzling over bread, she said.Extra light olive oil for cooking, as it's more stable, meaning it doesn't release harmful compounds when heated. I always have tinned sardines in tomato sauce in the cupboard as it is super tasty and less costly than fresh fish, Jackson said.