Food additives are substances that are added to food to make them taste better, look better and keep them fresh for longer. Some additives have been used for ages - like salt, vinegar and sugar. Others have been artificially created for our consumer society and are used in processed foods - which were practically non-existent in our ancestor's lives.
Looking at ingredient lists can be very confusing, to say the least. Some food items have that many additives, they couldn't be further from real food. And the majority of us have no clue what most of them are.
If you want to avoid artificial ingredients, eat fresh food - the least processed the better. And if you can't get fresh fruit & vegetables use frozen. Instead of buying ready-made and processed food, start cooking yourself - this way you control what's going in your meals.
That's not to say that all additives are bad. Many additives are harmless and keep our food safe, however some have the potential to cause you harm if consumed on a daily basis. Food additives go hand-in-hand with processed food, and we all know by now that in order to stay healthy and keep our weight in check, we should stay away from it.
Here is a list of additives to watch out for:
TITANIUM DIOXIDE
E171 – Titanium dioxide

Used in:
Chocolates, sweets, pastries, lollies,
chewing gum, white coating on donuts
Avoid because:
Possible adverse effects on the reproductive
system. The International Agency for Research on
Cancer (IARC) classifies titanium dioxide as a Group 2B carcinogen, which means it's possibly carcinogenic to humans.
Sulphites

E220 - Sulfur Dioxide
E221 – Sodium sulphite
Also: E222, E223, E224, E225, E228
Used in:
Wine, dried fruit, ready meals, pizza, orange juice, beer
Avoid because:
This preservative can cause asthma, headaches and breathing problems in people with sulphite sensitivities.
Nitrites
E250 – Sodium nitrite

E251 – Sodium nitrate
E249, E252
Used in:
Processed meat, bacon, smoked fish
Avoid because:
Has been declared as “probably carcinogenic" by the International
Agency for Research of Cancer.
BHA/BHT

E320 - BHA Butylated hydroxyanisole
E321 - BHT Butylated hydroxytoluene
Used in:
Chips, cereals, chewing gum, candy, vegetable oil
Avoid because:
Impacts the neurological system of the brain; alters behaviour and has potential to cause cancer.
CARRAGEENAN
E407 - Carrageenan

Used in:
Almond milk, soy milk, coconut milk, rice milk,
ice creams, nondairy desserts
Avoid because:
Can trigger inflammation, bloating, irritable bowel
syndrome, glucose intolerance, colon cancer, food allergies
MSG

E621 - MSG Monosodium Glutamate
Used in:
Chips, cookies, lunch meats, snack food,
Chinese food, frozen meals
Avoid because:
May result in depression, disorientation, eye damage,
fatigue, headache and obesity.
Aspartame

E951 – Aspartame
Used in:
“Diet” products, soft drinks, mints, sugar-free gum,
sweeteners like Equal and Splenda
Avoid because:
It is a neurotoxin and carcinogenic. May lead to depression,
headaches, brain tumour, diabetes etc.
Food colours

E102 – Tartrazine (yellow)
E104 - Quinoline (yellow)
E110 - Sunset yellow
E122 – Azorubine or Carmoisine (red)
E123 – Amaranth (purple)
E124 – Ponceau (red)
E128 - Red
E129 – Allura red
E133 – Brlliant blue
E142 – Green
E151 – Brilliant black
E153 – Carbon black E155 – Brown
Used in:
Ice cream, candy, bakery items, fruit cocktail, fruit juices, salad dressings
Avoid because:
May contribute to behavioural problems and hyperactivity in children and bring on allergic reactions. Animal studies have linked food colourings to cancer.
References:
WHO http://www.who.int/mediacentre/factsheets/food-additives/en/
Food Additives and Ingredients Association UK: https://www.faia.org.uk/food-colours/
Food Standards Australia New Zealand: http://www.foodstandards.govt.nz/consumer/additives/additiveoverview/Pages/default.aspx
Food Standards Agency UK: https://www.food.gov.uk/science/additives/foodcolours
European Food Safety Authority: http://www.efsa.europa.eu/en/topics/topic/food-additive-re-evaluations
Food Intolerance Network: https://fedup.com.au/factsheets/additive-and-natural-chemical-factsheets/220-228-sulphite-preservatives
Choice: https://www.choice.com.au/food-and-drink/food-warnings-and-safety/food-additives/articles/food-additives-you-should-avoid