A little background. I'm one month short of age 70 and struggling to lose weight. I am now 5'9" and was 5'10 1/2" when playing college football in the late '60s. Currently I'm at 192 lbs and was 185 lbs playing football. These days my weight is, shall we say, "distributed" differently. Not much belly fat but my jacket size has gone from a 40 to a 44. Nope, not lifting in the gym. But, to my question.....I've read a bit about a Ketogenic diet and am wondering what experiences others may have had with it. For the past couple weeks, maybe a month, I've been diligent about my calorie intake. I'm probably averaging about 2500 cals. a day. With good weather I'm riding more and in the past 10 days have done about 150 mi. at an average of 14 mph. This is with with significant climbing. What is puzzling me is my inability to lose weight. Not a lb. I feel good but am slow on climbs and attribute it to weight since even on the hardest output I don't get particularly tired and I recover really quickly. Could a ketogenic diet help me lose weight? Any other advice is appreciated.

I did a ketogenic diet for a while, and yes I lost weight.

I've talked to quite a few people that have had long term success with such a diet.

But in the end, I didn't feel my best on that diet nor did I feel like it was a good long term solution for me. I'm still working on the long term solution part, but I know that's not it.

The best diet is the one that lets you achieve your goals and one you can sustain for the rest of your life. Otherwise, it's only a temporary solution.

If you don't have a medical need (diabetes, other type of problem with insulin) this diet is pointless.

Weight loss comes from one thing: eating fewer calories than you burn. Unless you want surgery, that's it. The keto diet works for some people because it creates a calorie deficit for them. That's all there is to it. Massive restrictions to the thing most people like most has that effect.

A better option for most people is simply tracking your food intake and your exercise. There are web sites and apps set up to make this as easy as possible.

Personally, I think any diet that won't let you eat fruits and berries is ... suspect.

The quick loss of water weight in the beginning can be helpful psychologically, but it's not magic apart from that. Be sure to keep eating some fiber (green veggies have some carbs, but you're burning some off by being an active person.)

It's not surprising that you are gaining weight. Your BMR is around 1600. If you're eating 2500 a day that means you need to be burning an average of 800 calories per day on the bike plus other activity just to maintain your weight. 20 miles a day on the bike at 14mph is likely to be burning you about 500 calories, maybe less, I would guess this is just simple over-eating, or over-estimating your calories burned on the bike.

As you age, it's normal to lose muscle mass and for your resting metabolic rate to slow. This means that you need less calories and that weight gain is likely if you don't pay attention. Weight redistribution is also likely- carrying more weight as fat.

Also declining as you age is your VO2max, which is your rate of maximal oxygen utilization, which relates to speed & power.

Think about it: you're carrying more inert weight (in the form of body fat, at least muscle that you carry has some ability to produce work) in the context of a declining aerobic capacity (decreased power). It's normal to be slow.

There are ways to increase resting metabolic rate- building muscle through weight lifting is one. Getting yourself fit enough that you can do interval or threshold workouts is another- when you ride at >75% VO2max, your metabolism is higher for many hours afterward (in part because these workouts are damaging to the body, and your body is expending energy to rebuild itself post workout, so you really do need to be prepared for these by having lots of easy miles under your belt).

Doing some weight lifting now is likely your best immediate step. It will help you a lot to have more muscle.

As far as diets go, you really want to lose fat but be 100% paranoid about losing muscle. So do not restrict protein calories. Also be aware that severe calorie restriction, like 1200 cal/day or less, is proven to slow resting metabolic rate. So just don't go there, it is a poor approach in the long run.

You may need to simply restrict calories a little more, burn more calories with lots of slow cycling, hit the gym a few days a week, eat plenty of protein. After 6 months of that, your weight loss will stall and hopefully your fitness will be improved enough that you can pick up the intensity of your cycling, if your health otherwise allows it.

IMO don't go to a weird diet until you've done the basic stuff right.

If what you're doing isn't working then try something else.
Something like low carb/keto that has worked very well for many other people(+me)
should be worth a shot.

One thing NOT to do is try keto and continue ramping up exercise at the same time.
You'll feel like crap and swear keto was a total failure and the dumbest idea ever.
Ease off exercise for a week or two while your body adapts to burning a lot more fat and less carb.
Then you can increase the aerobic exercise. A high volume of high intensity exercise will always be a problem on low-carb

To lose weight I stick with 1500 cal/day. That averages about 2lb/week. More cals than that and progress can be too slow and discouraging. Even with that, there are times where loss seems to plateau for a couple of weeks.

With reduced intake, I try to eat foods with good nutritional value, that is food containing other important nutrients. Protein is important for active and older people to help forestall sarcopenia. I try to get around 100gm a day which accounts for 400 of the 1500 cal I eat when dieting. And by 100gm of protein, I'm mean spherically protein, not 100 cal of meat, fish etc, each of which would have less than 100 cal of protein.

What works for me likely won't work for many others.

How did you come up with that BMR? I did it using the Harris equation and I get 2557. This is based on moderate activity 3 days/wk. I'm just wondering if I've missed something.

^^^^This. Most people don't eat enough fiber in the "normal" (i.e., Standard American) diet, and folks on a ketogenic diet often end-up eating even less. What's more, most of the high-fat/moderate-protein foods -- dairy, in the main... cheese -- tend to gum-up the works, and are calorie-dense; we eat more of them, and get way more calories than we realize, or than we burn. I'm not a CICOpath (Calories-In, Calories-Out), but...

Wheat bran is very good -- a 1/4-cup is only 50kcal, with 6gr of fiber and only 10gr of carbs... it's easy to take in, and it keeps things moving freely (do remember to increase your fluid intake, as well).

That's not basal. Basal is caloric burn if doing no activities. Calories burned during activities are above and beyond basal rate.

Just wanted to say thanks for all the helpful responses. Probably not going to do the Ketogenics diet. I'll be going with limiting sugar, wheat bases foods and alcohol. Like in a serious way. Also going to see my ND and fellow cyclists to see if she can advise me. Thanks again.

I have been on a ketogenic diet because I'm a type 2 diabetic. I lost 50 lbs and dropped my a1c from 8.9 to 4.7. There are quite a few misgivings in this thread.
1. Calories in, calories out is a myth. What causes people to gain weight is too many carbs.
2. Even if your not a diabetic, a ketogenic diet is healthy for you because it reduces inflammation which makes you healthier and butter makes your pants fall off.
3. Ketogenic diet means you are a fat burner, not a carb burner. Fat burns slower and keeps you full.
4. Even if you don't go to a full ketosis diet, you can do yourself a world of favor staying away from processed foods.

Ah. Eliminate alcohol. I wouldn't restrict sugar used for fueling on the bike if necessary, but why would you take in sugar at any other time? Wheat restriction does nothing if you're not celiac. And you'd sure as heck know if you were. Whole wheat products are good for you. Vegetables and fruit are good for you.

I'm not celiac, but I can tell when I have more than a couple servings of wheat. I get headaches and feel achy the next day. I feel better when I avoid it.

My son acts like a drug addict with wheat and dairy products. It takes him about a week to stop craving those things after he's eaten them.

Everything you posted is at least partially incorrect.