No, they're not just for Halloween: try mashing pumpkin in place of potatoes, to up your nutrient intake.
'Pumpkins are a superb source of vitamin A and great for boosting immunity and fighting off infections as the cold weather creeps in,' says nutrition and weight loss expert Jane Michell.
'And don't discard the seeds. They're rich in dietary fibre and mono-unsaturated fatty acids, which are great for heart health.'
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They're available dried or in juice and sauces all year round – but from now until December, look out for fresh cranberries, too.
'These lovely berries are best enjoyed fresh as they retain maximum nutrients and taste this way,' says Jane Michell.
'They're high in vitamins C and E, plus bone-building manganese. They also contain a large array of phytonutrients – natural plant chemicals that help protect the body from harmful free radicals and offer anti-inflammatory and cancer-preventing properties.
‘What's more, they're the perfect low-calorie snack: half a cup of cranberries only contains 25 calories.'
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'Apples are in season and in abundance in autumn,' says health expert and NHS weight loss consultant Dr Sally Norton (www.vavista.com).
'A great on-the-go snack, they're packed with fibre to keep you feeling full, and natural sugar to give you a little boost. You can also use them in place of sugar to sweeten any homebaked treats.'
Another good reason to eat apples? It'll help you stick to a healthier diet in general. People who ate an apple before going to the supermarket bought 28 per cent more fruit and vegetables than those who didn't, researchers at Cornell University have found.
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The Christmas stocking favourites are tasty, easy-to-peel and usually seedless, which makes them very appealing as a fuss-free snack.
They're a good source of immunity-boosting vitamin C, as well as calcium and potassium. Use them to dress up autumn salads, too.
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Did you know that sweet potatoes count towards your recommended 5-a-day portions of fruit and vegetables, whereas ordinary potatoes don't?
'Sweet potato is packed with goodness and provides fibre, vitamins C and B6, and beta-carotene – an antioxidant powerhouse that prevents cell damage and converts to vitamin A in the body,' says Jane Michell.
'Cutting them into half-inch slices and steaming them for just seven minutes will bring out the flavour and maximise nutritional value.'
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This is one of the few leafy green vegetables that's more abundant during the colder months.
'It's seen by many as the “king of greens” because it provides protein, vitamins A, C, E and K, plus lutein – an antioxidant that promotes good eye and skin health,' Jane Michell explains.
'Keep it in a perforated bag in the fridge. It's best eaten soon after buying: as it grows older, it will become increasingly bitter. I recommend steaming it for maximum nutrition and flavour.'
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Now, don't pull that face: Brussels are good for you. Dr Sally Norton explains: 'Sprouts get a bad press at this time of year, but they really do deserve a place on your plate.
'Along with other cruciferous vegetables such as cauliflower and broccoli, they have the ability to lower cholesterol and fight inflammation. Some early studies show they may even inhibit some forms of cancer.'
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'Another seasonal staple to add to your autumn diet, butternut squash provides vitamins A and C, manganese, calcium and potassium,' says Jane Michell.
'It can be stored for up to three months in a cool, dry and well-ventilated place.'
Use it to make soups or eat it mashed or roasted in place of potatoes.
Try this delicious butternut squash recipe
They often get overlooked in favour of carrots at the dinner table – but these delicate, sweet-tasting root vegetables are a good source of fibre, vitamin C, calcium and iron.
Look for smooth, firm parsnips, rather than larger, coarser ones, which can be tougher to eat.
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Head out to the hedgerows now and you may just manage to grab the last of autumn's crop of ripe, juicy blackberries.
They're rich in vitamin C and have one of the highest levels of disease-fighting antioxidants of all fruits.
They taste great in pies and crumbles, of course – but for a super-healthy breakfast or dessert, Dr Sally Norton suggests adding a handful of blackberries to some protein-rich Greek yoghurt.
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