Most canned and frozen fruits and vegetables are processed within hours after harvesting.
The nutrient content is NOT comparable to fresh.
 Most canned products are loaded with preservatives and additives to prolong shelf life, which may cause intestinal bloating in GI tracts

If one has to use canned products then do the following

Sodium is usually added to canned foods to preserve them so look for low-sodium,
reduced-sodium, or no-salt-added labeled foods. Compare the sodium content on the Nutrition
Facts label, and choose the product with the lowest amount.
Drain and rinse canned veggies to reduce sodium even more.
Frozen vegetables with sauces and seasonings can have excess salt and added calories.
Look for fruit that is canned in water, its own juice, or light syrup. If the fruit is canned in light
syrup, drain and rinse before use.
Make sure frozen fruits are 100% frozen fruits – no added sugars.