Miracle foods are a staple of the media, as everybody hopes to find something to fix health problems. A few years back, it was olive oil and the Mediterranean diet. Now flaxseed oil has moved into the spotlight. Proponents of both olive and flaxseed oil claim benefits for heart health and lowered cholesterol. While both oils seem to be good for you, studies of many health claims are inconclusive.

Fats in Oils Fats come in different types, from the villainous trans and saturated fats, which have long been blamed for many health woes, to unsaturated fats like olive and flaxseed oils. These classifications refer to the way the hydrogen bonds are arrayed within the fat molecules. Monounsaturated fats such as olive oil may help control blood sugar and insulin levels and normalize blood clotting, according to Mayo Clinic.com. Unsaturated fats are linked to higher levels of HDL, or what’s called “good” cholesterol. But good or bad, all oils are high in calories, so keep your overall caloric intake in mind. Pouring olive oil on unhealthy food will not magically render it healthy.

Alpha-Linoleic Acids One of the reasons flaxseed oil has become so popular is because it contains alpha-linoleic acid. Your body converts ALA into docosahexaenoic acid and eicosapentaenoic acid, the omega-3 fatty acids you get from fish oil. This appears to be good news for vegetarians. Omega-3s seem to prevent arthritis and heart disease and reduce inflammation. However, researchers have not yet concluded whether the human body processes ALA in the same way as fish oil, so you may or may not reap the same benefits. The good news for ALA is that it seems to cut down on fatal heart attacks. You can also get ALA from eating walnuts or canola oil.

Lignans Flaxseeds also contain lignans, a chemical fiber that may help prevent cancer. Lignans are a plant estrogen, chemically similar to estrogen, the human hormone. Your digestive bacteria convert lignans into substances that might fight the formation of cancerous tumors. Lignans may also be antioxidants, substances which protect your cells from damage. Flaxseeds naturally contain lignans, but flaxseed oil does not. Some processors add lignans back in so that you can get these benefits from flaxseed oil.

Quality and Form You can buy flaxseed oil and take it by the spoonful, mix it into salad dressing or other foods or take it in capsules as a supplement. Both flaxseed and olive oil can become rancid. Flaxseed oil is especially delicate. It should be packaged in a dark-colored bottle and kept refrigerated. The best flaxseed oil is processed at a low temperature. The Berkeley Wellness Letter advises against taking flaxseed oil supplements, saying that effects at higher dosages are unknown. Producers of olive oil, with its long history, seem more reliable. However, a recent study at the UC Davis Olive Center uncovered questionable practices in the olive oil business. Some companies adulterate their “extra virgin” olive oil with cheaper refined olive oil or hazelnut oil, make their product from overripe or damaged olives or store the oil improperly, leading to oxidation, according to the UC Davis Olive Center. Olive oil should be stored in a room-temperature, dark cupboard, and consumed within six months of opening the bottle. Or you can store it in the refrigerator.

Risks Chemicals interact in surprising ways, so ask your doctor about possible interactions with medications before you take any supplement. ALAs and other omega-3s interact with blood thinners, cholesterol-lowering medications and steroids. Pregnant and breastfeeding women should skip flaxseed oil supplementation, as not enough research has been done to determine safety. Flaxseed oil might aggravate the conditions of people with bipolar disorder or schizophrenia.