If possible try to buy produce that is –
Fresh and/or in season
Free of added sugar (read the ingredients on the label). Avoid foods containing high fructose corn syrup or agave.
Free of hydrogenated vegetable oils and/or trans-fatty acids
Free of  artificial sweeteners like  aspartame, or any recommended here to avoid.
Free of chemical preservatives

All of the above is not always possible, so do the best you can! Your local health food store will be a good source of information in these matters.

Liver friendly foods

Raw and cooked vegetables of all varieties.
Vegetables that are highly liver cleansing are high in the mineral sulphur; these include cruciferous vegetables (broccoli, Brussels sprouts, cabbage, cauliflower, bok choy) and garlic, leeks, radishes, shallots, kale and onions.
Broccoli is a cruciferous vegetable, which contains healing phytonutrients such as indoles, thiols, and sulphur compounds, which enhance the detoxification pathways.

Sulphur is needed by the liver detoxification pathways. Vegetables high in sulphur help the liver to break down fats and pump them out of the body via the bile.
Fruits and vegetables with deep bright pigments such as orange, yellow, red, purple and green colours are very liver cleansing (eg. carrots, pumpkin, citrus fruits, purple cabbage, beetroot, red, yellow and green capsicums (bell peppers), cherries, plums etc - these pigments and phyto-chemicals are powerful healing antioxidants for the liver. Over a period of a week you should aim to eat a wide variety of fruits and vegetables so that you “eat the rainbow”.
Alfalfa, barley leaf, wheat grass, kale and spinach and indeed any dark green coloured vegetables can be eaten or juiced, or taken in powder form, to give your liver a boost of chlorophyll, which is the green pigment that gives plants their colour; chlorophyll acts as both a liver tonic and a liver cleanser.
Avocados and olives provide healthy fatty acids for the liver, so include them regularly in your diet.

Raw fruits of all varieties. The best fruits for the liver are those that have a tart taste because they contain organic acids; these organic acids will lower blood levels of sugar and insulin and help you to burn fat. They also help to cleanse the liver. Fruits that have a tart taste include all types of citrus fruits, all types of berries (strawberries, blackberries, blueberries, raspberries, etc), cherries, kiwi fruit, persimmons and stone fruits. If you are trying to lose weight, avoid or go very easy on the bananas, mangoes and grapes. Dried fruits are delicious and generally healthy; however they are much higher in carbohydrate, so if you are trying to lose weight, go easy on the dried fruits.

Sea weeds or sea vegetables are very healthy and are eaten in huge amounts by some Asian cultures. The culinary varieties include arame, wakame, nori, dulse and kombu. Seaweeds are high in health-promoting minerals and they also help to chelate (bind with) and remove toxins and heavy metals from the bowels.

Nuts of all varieties provided they are fresh – meaning unroasted and unsalted. Examples are almonds, macadamias, pistachio, cashews, walnuts and Brazil nuts.

Seeds such as flaxseed (linseeds), sunflower, sesame, pumpkin seeds.

Legumes - these consist of beans of all varieties, lentils and chickpeas. These can be eaten cooked in soups, stir fries or salads or sprouted.

Sprouts – such as alfalfa, mung bean, wheat grass, barley grass etc are a good source of protein and chlorophyll which is liver cleansing.

Poultry – turkey, chicken, duck, etc - preferably free range and don't forget to remove most of the skin.

Eggs - preferably organic or free range.

Seafood such as oily fish (tuna, salmon, sardines, mackerel), fresh fish fillets, shellfish. Canned seafood is healthy. Avoid eating seafood raw, smoked or deep-fried.

Spreads for breads/biscuits- hummus, tahini, nut spreads (Brazil, almond, cashew, natural peanut paste etc), fresh avocado, pesto sauce, Baba ganoush, salsa, tomato paste, olive paste and aioli. Make sure that the spreads you buy do not contain hydrogenated vegetable oils or sugar. Butter is much healthier than margarine, but it should only be used as a special treat and must be very fresh, as rancid butter is oxidized and is bad for the liver.

Stocks and flavourings – miso paste, soy sauce, tamari, all fresh herbs, organic vegetable and meat stock cubes, V 8 vegetable juice, tomato paste.

Oils - Cold pressed unrefined vegetable, nut and fruit oils are the healthiest - eg. Virgin olive oil, avocado oil, virgin coconut oil and macadamia nut oil.
Coconut oil can be used for Asian stir fries if you want the tropical flavour.

Vinegars – the best of all is apple cider vinegar, other healthy vinegars are red wine, balsamic and sherry vinegar.

Beverages: unsweetened soy milk, almond milk, oat milk, rice milk, canned coconut milk (needs diluting with water), water (filtered or purified), freshly made vegetable juices, or canned tomato juice with no added sugar, tea (regular, green or herbal). Coffee is allowed as it comes from a natural source – the coffee bean. Ground unprocessed coffee is much healthier than instant coffee. Do not drink more than 2 to 3 cups a day, as there are substances in coffee (especially the caffeine) which over stimulate the step one detox pathway in the liver.

Herbs and Spices are generally good for the liver- these include jalapeno pepper, celery seed, celery leaf, peppercorns, chervil leaf, anise and aniseed, chilli, ginger, coriander (cilantro) leaf, coriander seed, curry, cayenne, bay leaves, caraway seed, lemon grass, thyme, marjoram, mustard seed, turmeric, basil, chervil, parsley, paprika, nutmeg, lemongrass, dill leaf and seed, thyme, oregano, sage, garlic, cloves, chives, fenugreek, cardamom, poppy and sesame seeds, horseradish, wasabi, mace, stevia, cloves, cassia, pimento, cumin seed, galangal, cinnamon, saffron, rosemary, mint, fennel leaf and seed, green tea and others if they are natural.
These herbs and spices are especially helpful because they speed up the detoxification process inside the liver cells. Thus, they are cleansing and fat-burning foods.

Sweeteners – the naturally sweet herb stevia is the best sweetener of all and is 300 times sweeter than sugar; thus only tiny amounts are needed. Stevia has zero calories and has no effect upon blood sugar levels. Stevia extract is available in the form of powder, tablets and drops from your local health food store. You can also grow your own stevia plant and use the leaves to sweeten dishes and drinks. Nature Sweet is better than sugar, and is calorie free and so has less effect upon blood sugar levels. Stevia and Nature Sweet can be used in tea and coffee and in cooking in preference to sugar.

In general in those with a fatty liver it is best to minimize the use of foods that are made from grains, especially if the grains are combined with sugar and/or hydrogenated vegetable oils.
In my patients with a very fatty liver and/or type 2 diabetes, I find it is essential that they avoid ALL GRAINS AND SUGAR until their problem is under control; this may vary from 3 months to 6 months. In those who find that their weight will not budge an ounce, it is also effective to choose a grain free and sugar free diet for at least 3 months.

In those who find it impossible to lose weight the elimination of ALL grains (wheat, rye, barley, oats, rice, corn) and their products, often make it possible to kick start the fat-burning process. In my type 2 diabetic patients I have found that the total elimination of all grains and sugar from the diet may reverse the diabetes.
But if you do want to eat some foods containing grains and/or flour these types are the best:
Grains - buckwheat, rye, barley, oats, quinoa, amaranth
Flour – buckwheat, soy, quinoa, pea
Breads - whole-grain, multi-grain, stone ground, pita, sourdough
Biscuits - crisp breads and crackers made from whole-grains; they must be free of hydrogenated vegetable oils and sugar.