There are so many healthy fat alternatives we're supposed to be eating – such as avocado, flax, chia and coconut oil. Are they all equally good for me? How much can I include in my diet without gaining weight?
For years we were told to eat less fat to avoid high blood cholesterol, heart disease, obesity, even certain cancers. But over the past decade, we've emerged from a low-fat culture to one that embraces so-called healthy fats. Eating too little of these fats can rob your diet of key nutrients and may, potentially, harm your health.
There's plenty of evidence that certain fats, called unsaturated fats, have health benefits. Monounsaturated fats – plentiful in olive and canola oil, almonds, peanuts, hazelnuts and avocado – may help lower LDL (bad) cholesterol, raise HDL (good) cholesterol, reduce inflammation and, among people with diabetes, improve blood sugar control.
Polyunsaturated fats found in flax, chia and hemp seeds, and in many cooking oils (such as sunflower, safflower, grapeseed, canola, walnut), deliver essential fatty acids the body can't make on its own. Higher intakes of one such essential fat, called alpha-linolenic acid (ALA), has been tied to a lower risk of heart disease, stroke and Type 2 diabetes.
Polyunsaturated fats can also help lower LDL cholesterol when they're substituted for saturated fat, the type that's found in butter, cream, cheese and fatty cuts of meat.
Saturated and trans fats have long been considered unhealthy fats that, when eaten in excess, raise LDL cholesterol and increase the risk of heart disease. Trans fats, found in foods made with partially hydrogenated vegetable oils (crackers, cookies, pastries, muffins, snack foods, fried foods) also lower HDL cholesterol and are thought to increase the risk of Type 2 diabetes.
Recent research, however, has stirred up controversy over the link between saturated fat and heart disease, suggesting the real culprit is our steady intake of refined carbohydrates. Even so, heart health guidelines remain the same: Eat a diet rich in fruits, vegetables and whole grains and, importantly, include healthy, unsaturated fats.
The downside with healthy fats – like all dietary fats – is that they are calorie-dense, making it easy to blow your calorie budget if you eat too much of them. Consider that one tablespoon of oil delivers 120 calories, two tablespoons of nut butter have 190 calories, and two tablespoons of seeds add 90 calories to your diet. Eat half an avocado and you'll consume about 160 calories.
A healthy diet can derive 20 to 35 per cent of its calories from fat. For a 2,000-calorie diet, 400 to 700 calories can come from fat, which translates to 44 to 78 grams of fat a day. If you're following a 1,500-calorie weight-loss diet, you can eat 300 to 525 calories from fat, or 33 to 58 grams. (One gram of fat contains nine calories.)
To prevent weight gain, consider your total daily calorie intake before tossing avocado into a salad, sprinkling hemp hearts over oatmeal, blending almond butter in a smoothie, or stirring ground flax into yogurt.
Compensate for the extra calories by cutting out refined carbohydrates such as white bread, crackers, cereal bars, white rice and sweets. Substitute unsaturated fats for saturated ones, such as nut butter on toast instead of butter, hummus in sandwiches instead of cheese, and seeds on a salad instead of bacon bits.
It's packed with monounsaturated fat and vitamin E, an antioxidant that boosts immunity. It's also a decent source of calcium and magnesium, minerals important for bone health and blood-pressure control. Per tablespoon: 98 calories and nine grams fat.
Rich in monounsaturated fat, this fruit also delivers fibre (seven grams per half), folate and potassium. Plus, it's a source of lutein and zeaxanthin, phytochemicals that guard against cataract and macular degeneration. One-quarter avocado: 80 calories, seven grams fat.
Cultivated in Canada, this unrefined oil is rich in monounsaturated fat, the omega-3 fatty acid alpha-linolenic acid (ALA) and vitamin E. Its high smoke point – the temperature at which an oil starts to burn – makes it able to withstand high heat (sautéing, stir-frying, pan frying). Per tablespoon: 130 calories, 14 grams fat.
A source of polyunsaturated fat, chia seeds are an exceptional source of ALA and deliver fibre, calcium, magnesium and potassium. Per tablespoon (ground): 33 calories, 2.5 grams fat.
Despite its high saturated fat content, studies show it raises HDL (good) cholesterol. It also contains medium-chain triglycerides, fats that may promote satiety and increase calorie-burning in the body. (There's limited evidence coconut oil will help you lose weight.) It's well-suited for high-heat cooking. Per tablespoon: 117 calories, 14 grams fat.
Also called flax meal, it's high in ALA and contains fibre and lignans, phytochemicals linked to breast and prostate cancer prevention. Per tablespoon: 37 calories, three grams fat.
A source of essential fatty acids (including ALA), protein and fibre, hemp hearts are also a good source of magnesium. Per tablespoon: 56 calories, 4.3 grams fat.
They're a great source of monounsaturated and polyunsaturated fats along with vitamin E, magnesium and potassium. Per tablespoon (raw): 45 calories, four grams fat.