Whole foods are the least processed foods. The lack of processing allows the food to keep most of the nutrition. Whole grains like whole wheat, oats, barley and brown rice are good sources of dietary fiber and other nutrients not present in their refined forms, so are the best choices for eating healthy.
Here’s some information.
Bottled Juice
In bottled juice processing, the fruit is separated from its fiber, pasteurized and mostly added with preservatives. Lacking fiber, the sugar in juice enters the bloodstream much faster, and hence affects insulin levels; pasteurization decreases vitamins content to some extent; and preservatives like brominated oil has been linked to major organ system damage, birth defects and growth problems. For eating healthy, you’d better make your own juice with a super blender that crushes all the fiber in the fruit or, better still, have fresh fruits.
Homogenized Milk
Mechanical homogenization exposes milk to high heated or pressured processing that may damage its fat particles so the body cannot break them down, increasing the risk of rancidity and oxidation which may contribute to heart disease. Easily separated creams in pasteurized or fresh milk may be inconvenient, but they are better choices for eating healthy
Canned Foods
Cooking in canned foods processing destroys about one-third to one-half of the vitamins A and C, riboflavin and thiamin, 5% to 20% more are lost during storing. Salt and preservatives addition may harm the body furthermore. Fresh foods are more nutritious than canned or frozen ones, so more suitable for eating healthy.
Cooking Oil
In most cooking oil extraction the seeds are subject to crushing, high heating and heavily pressing that damage naturally occurring vitamins, like Vitamin E, and produce dangerous free radicals. Toxic solvents, usually hexane, are sometimes used to increase yield and may still remain in the oil up to 100 parts per million after boiled off. High heat processing also produces residues coming off the metal containers used. Your choices for eating healthy are cold-pressed extracted oils, such as olive and coconut oils.
Instant, Refined, Enriched and Fortified Foods
Instant food processing converts naturally occurring soluble fiber into an insoluble form, which may cause unnecessary spikes in blood sugar. This also happens to refined foods. The refining process also removes or destroys many vitamins, minerals, enzymes, and other nutrients. "Refined" foods, such as white flour and white sugar, significantly reduce B vitamins in the body.
Enriched and fortified are only made up strategies to compensate processing lost while increasing shelf life, color, flavor, smell, consistency, or convenience. The additives are oftentimes of lower quality. Pasteurized milk is fortified with synthetic Vitamin D (D2), which many children react to while the natural form (D3) helps inhibits skin and prostate cancer, stimulates bone density, and increases the absorption of Calcium and Phosphorus.
For eating healthy, forget about convenience and have more whole, raw, or unprocessed foods.
However some traditional processing turns our foods into better choices of eating healthy, for example:
Fermented Foods: Sauerkraut
Traditional lacto fermentation helps keep vegetables edible without freezing or canning. The process increases the foods’ nutrition, produces probiotics that promote healthy flora in the body and converts natural sugars and starches to lactic acid; so it’s better for health, flavor and taste.






