The best way to build up the adrenals is with natural vitamin C, pantothenic acid, and adaptogenic herbs.
For vitamin C I like papaya, watercress, berries, and kiwis for food sources. Herbal sources include amla, acerola cherry, rosehips, and nettle leaf.
For pantothenic acid the best source is bee pollen. Nutritional yeast, rice bran, oat bran, nettle leaf and seaweeds are also good choices.
Some of the best adaptogenic herbs include schisandra berry, Chinese licorice root, astragalus, Siberian ginseng, jiaogulan, and ashwagandha. Nettle leaf and amla berry are also excellent for the adrenals.
Try to avoid stress as much as possible. Also stay away from pharmaceutical steroids and all stimulants like caffeine and nicotine. Keep in mind that caffeine can be found in many hidden sources including aspirin, kola nut (bissy nut) and guarana (extremely high). I also recommend avoiding adrenal glandulars as these can atrophy the adrenals with long term use.
Most people using the adaptogens, vitamin C and pantothenic acid generally report improvement in as little as 3 days.