A good skin reflects a healthy lifestyle. One can delay the ageing process by eating healthy which also gives boost to a good skin. Processed or refined sugars and food with high glycemic index should be consumed in moderation as they cause skin inflammation, irritation and breakout. And yes supplements are not a substitute for a healthy diet. One can nourish the skin by eating fruits, nuts, grains, vegetables, fatty fish and legumes. Incorporating healthy foods in the diet can help to skip the photo filter and bring out natural beauty.
Here are a few nutrients that benefit the skin:

Omega 3 fatty acid: Keeps the skin hydrated and reduces inflammation in the body.It also preserves collagen in the skin and makes it firmer. The top source of omega 3 is fish like Salmon, Tuna, Sardines. For people who don’t eat fish the plant derivatives rich in Omega 3 are Flaxseeds, Almond and Walnut, Chia seeds ,Canola or Soyabean oil.

Lycopene: Tomatoes are a rich in lycopene, an antioxidant which helps to keep the skin smoother. And also protect the skin from UV damage Tomatoes can be incorporated easily in many dishes like salads, side dishes, sandwiches ,sauces etc.

Vitamin C: Vitamin C helps fight wrinkles and hence reduces the signs of ageing, Some of the best foods that are rich in Vitamin C are Citrus Fruits( Oranges, Lemons, Lime, Grapefruit etc),Bell peppers, Broccoli, Strawberry, Kiwi.

Vitamin E: Its an antioxidant that prevent cell damage .Some vitamin E rich foods include: Almonds, Sunflower seeds

Polyphenols: They are powerful antioxidants. Some rich sources are:Berries,Cocoa powde,nuts,flax seeds, olives, coffee, tea, fruits like pears ,apples, peaches, plums etc

Tea and Coffee: They prevent hyperpigmentation and photo aging.

Grapes: They contain Resveratrol which is highly beneficial for the skin.

Dark Chocolate: they contain Flavanol which improves the texture of the skin and also protect against sun damage.

Pomegranates: they contain polyphenols which fight free radicals thus helping to regulate the skins blood flow ,giving it a nice healthy glow.
Some other foods that are beneficial for the skin are:

Watermelon: Though watermelon has higher concentration of water it helps to reduce the puffiness under eyes that is caused by water retention and due to its low sugar it doesn’t compromise collagen that leads to fine lines on wrinkles when depleted.

Green Tea: It has anti oxidant and anti inflammatory properties and can be used as a great toner to treat acne. It contains vitamin K that helps lighten dark circles under the eyes. Its great for healing blemishes and scars, flushes out toxins and keeps skin plump.

Carrot: It has beta carotene which is a main active ingredient in Retin A. It decreases the skins oil production and improves psoriasis.

Eggs: Amino Acids present in eggs and meat are the important building blocks of collagen production.

Kidney Beans: Along with being protein rich kidney beans are also rich source of zinc which in turn has healing properties that help in overcoming acne .

Soy: It contains isoflavones which improve the skin dryness and increase collagen which keeps the skin smooth and strong. Also protects the body from UV radiation.

Yogurt: It is a probiotic with anti inflammatory and improves the symptoms of acne,atopic dermatitis and psoriasis.It can help with skin sagging and increase skins hydration.