Avocados are rich in monounsaturated fatty acids, dietary fiber, potassium and phytochemicals. People who eat avocados tend to have lower BMI, body weight and waist circumference than people who skip this green superfood, per a study in Nutrition Journal. While avocados are higher in calories than other fruits and vegetables, their satisfying fat and fiber combo may help you slim down. Add some to your salad, sandwich or taco night for a burst of creaminess and flavor.

Fruit gets a bad rap sometimes because it naturally contains sugar. But eating fruit can help you lose weight, especially when you swap in fresh fruit for processed foods or other unhealthy snacks. You'll get a naturally sweet treat, plus reap the benefits of fiber and antioxidants. A recent study published in the Journal of Nutrition found that higher fruit consumption was associated with lower risk of becoming overweight or obese, independent of vegetable or fiber intake—though including fruit as part of a healthy diet overall is always the best strategy.
Those issues can be part of what's known as the “keto flu,” Warren says. Other side effects of the keto diet, all of which are tied to carb withdrawal, can include lightheadedness, nausea, mental fog, cramps, and headaches, in addition to tiredness. Luckily, the keto flu doesn't usually last more than a week—which is coincidentally about when people start to see the number on the scale go down, says Warren.
Yogurt is protein-packed and full of probiotics, which are good for gut health and may help your weight-loss efforts. Your gut health can impact your weight, and eating more fiber and probiotics helps keep your gut bacteria happy, which can be good for your metabolism (read more about your gut-weight connection). Go Greek for more protein; plus, research from Appetite found that consumption of Greek yogurt was associated with reduced appetite and increased satiety. Just keep an eye on added sugars in flavored yogurts, which only add calories. Instead, use fresh fruit to sweeten plain yogurt.
A keto diet has shown to improve triglyceride levels and cholesterol levels most associated with arterial buildup. More specifically low-carb, high-fat diets show a dramatic increase in HDL and decrease in LDL particle concentration compared to low-fat diets.3A study in the long-term effects of a ketogenic diet shows a significant reduction in cholesterol levels, body weight, and blood glucose. Read more on keto and cholesterol >

When a person goes off the ketogenic diet and regains much of their original weight, it’s often not in the same proportions, says Kizer: Instead of regaining lean muscle, you’re likely to regain fat. “Now you’re back to your starting weight, but you no longer have the muscle mass to burn the calories that you did before,” she says. “That can have lasting effects on your resting metabolic rate, and on your weight long-term.”
Going gluten-free may be a popular trend, but unless you're actually gluten-intolerant or have celiac disease, plenty of reasons exist to continue eating whole grains. They're a tasty way to fill up on both soluble and insoluble fiber, which help you feel full for longer and keep bowel movements regular (oats, barley, and bulgur are especially high sources). Whole grains can also help prevent weight gain: in one study, women who ate whole grains like wheat germ and dark bread had a 49% lower risk of "major" weight gain over time.
A systematic review in 2018 looked at sixteen studies on the ketogenic diet in adults. It concluded that the treatment was becoming more popular for that group of patients, that the efficacy in adults was similar to children, the side effects relatively mild. However, many patients gave up with the diet, for various reasons, and the quality of evidence inferior to studies on children. Health issues include high levels of low-density lipoprotein (LDL), high total cholesterol, and weight loss.[23]
Because the ketogenic diet alters the body's metabolism, it is a first-line therapy in children with certain congenital metabolic diseases such as pyruvate dehydrogenase (E1) deficiency and glucose transporter 1 deficiency syndrome,[34] which prevent the body from using carbohydrates as fuel, leading to a dependency on ketone bodies. The ketogenic diet is beneficial in treating the seizures and some other symptoms in these diseases and is an absolute indication.[35] On the other hand, it is absolutely contraindicated in the treatment of other diseases such as pyruvate carboxylase deficiency, porphyria and other rare genetic disorders of fat metabolism.[9] A person with a disorder of fatty acid oxidation is unable to metabolise fatty acids, which replace carbohydrates as the major energy source on the diet. On the ketogenic diet, their body would consume its own protein stores for fuel, leading to ketoacidosis, and eventually coma and death.[36]
I know it's cliché, but let me get specific: When I arrive at a party, I don’t go immediately to the food. I first think about how many hours I plan on being there and try to pace myself accordingly. If I know it’s a three-hour buffet dinner, I may not start eating until an hour into being there. I’ll focus on drinking lots of water first and talk to people, so I don’t stuff my face too early and overdo it.
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