One of the most common questions that people ask when they’re trying to lose weight or improve their health is simply, “what should I eat?” With all the seemingly contradictory nutritional information available, it’s no surprise that there’s so much confusion around what to eat. But the answer isn’t that simple. That’s because more and more research is indicating a simple but previously elusive truth: there is no one diet that works for everyone. Hundreds of different genetic variants affect the way we process food, use energy, and store excess energy in our bodies (often in the form of fat).

Based on these genetic variants, people generally fall into one of four ideal diet types: low carb, low fat, Mediterranean, or balanced. Variations can exist within each of these diet types — for example, someone who is genetically predisposed to have lower levels of vitamin B12 may be advised to include more animal products such as fish, meat, poultry, and eggs in their diet — or take a vitamin B12 supplement if they’re a vegetarian. Regardless of which diet type you fall into, however, there are several universal guidelines for healthy eating that will benefit anyone looking to lose weight or improve their health.

Eat lots of plants

We all know that fruits and vegetables are good for us, but most of us don’t get enough of them in our diet. Make it a point to include plant foods in every meal. Whole foods — foods as close to their natural form as possible — are best. That means, no, you can’t count the blueberry bagel you had for breakfast or the fruit chews you ate for an afternoon snack.

When it comes to fruits and vegetables, choose non-starchy foods whenever possible (leafy greens and berries are better than corn and potatoes). Also try to eat a variety of colors. The same compounds that give fruits and vegetables their vibrant colors also give them many of their beneficial properties. One good way to get an abundance of different colors in one meal is to make a vegetable stir-fry: include purple cabbage, colorful bell peppers, broccoli, cauliflower, carrots, or whatever else you have on hand, and cook with shrimp or chicken.

Buy the best quality food you can afford

Food quality matters. Organic fruits and vegetables contain fewer harmful pesticides, are often fresher, and tend to have higher concentrations of beneficial compounds. Buying directly from growers at local farmers’ markets is also a great option. You can talk to the growers directly about their farming practices; many refrain from using harsh chemicals even if they aren’t certified organic.

Grass-fed beef is also healthier than factory-farmed meat. Grass-fed beef contains heart-healthy omega 3 fatty acids and more antioxidants, while factory-farmed meat contains inflammatory omega-6 fats.

If you can’t afford to buy organic or if organic foods aren’t available in your area, use resources like the Dirty Dozen list to help you identify the foods with the most and least contaminants.

Avoid sugar

Sugar is hazardous to your health, and it’s in a lot more foods than you might expect. Sugar ages the skin, suppresses the immune system, feeds tumor growth, and contributes to inflammation. Get in the habit of reading food labels and avoid foods with added forms of sugar, which include sucrose, dextrose, maltose, fructose, high-fructose corn syrup, corn syrup solids, cane juice, fruit juice concentrate, brown sugar, and molasses.

Try using natural sugar substitutes such as stevia, erythritol, xylitol, or monk fruit sweetener. Avoid artificial sweeteners such as aspartame and sucralose (Splenda), which pose their own health risks.

Avoid processed food

Generally speaking, the longer a food’s shelf life, the less healthy it is. Many of the chemicals used for food manufacturing and preservation simply don’t belong in your body. Get in the habit of read ingredients. If you don’t recognize something or can’t pronounce it, leave it on the shelf. The healthiest foods are those that don’t even have labels (again, fruits and vegetables).

Don’t fear the fat

Dietary fat has been demonized in the past several decades, and it’s second nature for many of us to reach for fat-free or low-fat foods. But you need fats in your diet. Fats are necessary for many processes throughout the body. Fats help build cell membranes, aid in muscle movement, and help prevent heart disease. Don’t be afraid to reach for foods like fatty fish, olive oil, avocados, nuts, and coconut oil. And be careful with those low-fat foods: they typically have sugar added to make up for the flavor that’s lost when the fat is removed. You’re usually better off getting the real deal.

One type of fat that you do want to avoid is trans fat, which is found in many baked goods (look for partially hydrogenated oil in the ingredients).

Avoid inflammatory foods

Inflammation has been linked to every major degenerative disease, and many of the foods in the standard American diet contribute to inflammation, including factory-farmed meat, sugar, wheat and other refined grains, fried food, soda, and dairy products. What fights inflammation? Omega-3 fatty acids, fruits and vegetables, green tea, olives, leafy greens, green tea, nuts, and seeds.

Find out what works for your body

The healthiest diet is one that’s tailored to your individual genetic makeup. You can discover your ideal matching diet type with Vivaliti DNA. We analyze 80 different genetic markers to give you a complete picture of how your body responds to different foods, which exercises are most beneficial for you, and other factors that will help you meet your health and wellness goals. Order your genetic test today!